Draft: Replace the render-function bootstrap-vue implementation with Vue-3-portable templates

Replace the render-function bootstrap-vue implementation with Vue-3-portable templates

⚠️ Disclaimer: 100% AI-generated

Every line of code, test, and this description was written by Claude (Opus 5.5) in Claude Code, directed and supervised by @xanf, with no hand-written code. Correctness claims rest on machine-checked evidence (markup/event parity fixtures rendered by main, the unit suites, Storybook pixel comparison, the Cypress suite, and GitLab's full jest + rspec suites via the integration MRs), not on human review.

This is one draft MR on purpose: it carries the whole series so it can be evaluated end to end. Every commit is one future small MR (see Splitting strategy). Status: complete. 87 commits on main bbb9a511ed; the vendored src/vendor/bootstrap-vue directory is gone.

What this does

Removes the vendored bootstrap-vue (BSV) render-function / functional / mixin implementation from @gitlab/ui and replaces it with Options-API SFCs with <template>s, written so that the library can move to Vue 3 without @vue/compat with minimal changes.

• The vendored tree is deleted. No importer is left, dist/vendor is gone and npm pack ships no bootstrap-vue path. The derived SCSS stays in src/scss/bootstrap_vue, with the BootstrapVue license notice next to it. vue-functional-data-merge is dropped (popper.js and portal-vue stay, src uses them), and so are the ui:bootstrap-vue CI jobs.
• Where the code went. Dropdown and its items, tabs, form select, tooltip, popover and the tooltip directive are inlined into their GlX SFC. Modal, table, table lite and form group keep an internal template SFC with the BSV name (BModal, BTable, BTableLite, BFormGroup), so consumer test contracts (stubs, findComponent({ name }), $children[0]) keep working.
• Pure refactor. No prop, event or slot is removed. 45 changesets: 41 patch, 4 minor (new public methods and the GlTable items provider type), no major. Vue 2 output is identical modulo comment placeholders and the deviations under Known differences; under @vue/compat behaviour only moves towards Vue 2.
• Size. 533 files, +49 434 / −51 984 against main.

Companion MRs: the native Vue 3 package !6551 and the GitLab MRs under Consumer follow-ups.

How the code stays portable

• One version shim, src/utils/vue_utils.js, holds every Vue-version-specific line: attrs and listeners (getAttrs, getListeners, getNonFallthroughListeners, getUndeclaredRootListeners, getRootClassStyle incl. compat .native routing, getComponentRootClassStyle), slots (getSlot, hasSlot, getNormalizedSlot, SlotOutlet, …), uid, reactive set/delete, ARRAY_WATCH_OPTIONS, scope id, isNativeVue3, defineDirective, mountComponent, transition class props, owner events, and the vModelDynamic backfill from the vendored vue.js. Branches select at runtime; under @vue/compat the native Vue 3 branch runs, so the existing Vue 3 jest lane exercises it.
• Root event bus (bv::*, ~110 call sites in GitLab) isolated in src/utils/root_events.js (Vue 2/compat: the $root bus; pure Vue 3: a per-app emitter).
• src/utils/vue_teleport.js: Teleport shim. Its Vue 2 branch is the ported BVTransporter; its Vue 3 branch renders the built-in Teleport once the target exists and, like portal-vue, nothing (and no warning) before.
• Render functions left: only inside the shims, namely the Teleport shim and SlotOutlet. The Vue 2 Teleport branch and SlotOutlet are deleted at the Vue 3 switch (built-in Teleport, native <slot>).
• Lint guard: PORTABLE_VUE_FILES in eslint.config.mjs (39 entries, every file that replaced vendored code) forbids render functions, functional, mixins, extends and Vue-2-only instance APIs outside the shims.
• Template rules, avoided explicitly: keyed <template v-for> (the two compilers disagree), .native, .sync, falsy attribute bindings, accidental whitespace text nodes (strict-whitespace prettier override where markup is whitespace-sensitive), refs inside v-for (normalised: unpatched compat ignores refInFor), slot presence cached in computeds, template refs named like state.

Evidence (tip 9224b1a3bb)

Layer	Result
Unit suite, Vue 2	6255 passed / 1 skipped
Unit suite, Vue 3 @vue/compat	6434 passed / 3 skipped
Markup + event parity vs fixtures rendered by main (Vue 2), 1615 scenarios	0 strict differences; 24 accepted (intended, see Known differences); 101 HTML-snapshot-only (comment placeholders)
Same, Vue 3 compat lane	0 strict differences; 581 scenarios converge to Vue 2; 43 accepted; 814 snapshot-only
Hybrid lane (Vue 2-compiled templates on the unpatched compat runtime)	0 new render errors; 38 errors that main has are gone
Storybook pixel comparison, 491 stories × vue2 / vue3 / hybrid, 1 px threshold	491/491 ×3
Cypress e2e (vue2 / vue3 / hybrid)	77/77 ×3
Build and dist	yarn build ok; 248 JS files, none under vendor/, every relative import resolves; compared with main's dist only dist/vendor (removed), 9 utility modules and 4 Storybook-only tailwind.css rules differ; yarn install --frozen-lockfile ok
Lint and messages	eslint, prettier, stylelint (0 errors), markdownlint clean; subjects and body lines ≤ 72; Danger emoji check clean
design.gitlab.com CI	green: https://gitlab.com/gitlab-org/gitlab-services/design.gitlab.com/-/pipelines/2977268471 (only the allow-failure code_quality infra job fails)
GitLab full jest + rspec	green, see GitLab

Every commit passes jest (both lanes), parity, the hybrid lane and lint on its own.

GitLab

GitLab with this series' package (ui:build_package of this MR) and the consumer changes listed under Consumer follow-ups, with pipeline:run-all-jest and pipeline:run-all-rspec: gitlab-org/gitlab!264170, pipeline https://gitlab.com/gitlab-org/gitlab/-/pipelines/2977009348.

Suite	Result
jest (Vue 2 11/11, Vue 3 compat 11/11, with fixtures 2 + 2, integration 1 + 1)	all green
rspec (unit, integration, migration, background migration, frontend fixtures, clickhouse/es9 variants)	all green
rspec system pg17 / rspec-ee system pg17	27/27, 15/15
e2e child pipelines	green

Red jobs, unrelated to this change and red on every integration MR: untamper-my-lockfile (cannot parse the package tarball URL in yarn.lock), the start-as-if-foss bridge, and allow-failure bundle-size-review / pajamas_adoption. Commit 87 is spec-only and does not change the package.

Native Vue 3

Package !6551 (packages/gitlab-ui-vue3): derived from this branch by a sync script plus codemods (lifecycle renames, compatConfig pins, shim on native Vue 3), jest (vue3-jest + VTU 2) and rollup, no @vue/compat. Synced from this series (no vendored code left):

Check	Result
Native jest	195/195 suites, 6098 passed / 0 failed; the 32 skips are the specs' own native gates (.native, Vue.extend, $root.$on)
Hand-edited specs	1 (base_dropdown.spec.js); every other spec runs as written here
Parity vs the Vue 2 fixtures (140 modules)	97 identical, 43 differ; every difference is what this series renders under @vue/compat or inherent to native Vue 3 (.native, attributes bound to false, legacy self-events)
Build and CI	247 dist files, ES2018 check ok; ui-vue3:unit_tests and ui-vue3:build green

GitLab Vue 3 MR gitlab-org/gitlab!264182, the analogue of gitlab-org/gitlab!246445 (closed) on the new package (no test-runner migration): assets compiled against the package, pipeline:run-rspec-vue3, a native jest lane. Pipeline https://gitlab.com/gitlab-org/gitlab/-/pipelines/2977350195 is green, against 246445's latest https://gitlab.com/gitlab-org/gitlab/-/pipelines/2688844024:

Lane	gitlab MR 264182 (this rewrite)	gitlab MR 246445 (hand-ported package)
compile-test-assets vue3 (+ production vue3 compiles)	green	green
rspec system pg17 vue3	27/27 shards	29/32
rspec-ee system pg17 vue3	15/15 shards	15/16
native jest (jest vue3 gitlab-ui-vue3 + fixtures)	13/13 shards	not in CI
compat jest baseline	13/13 shards	13/13

GitLab-side changes in that MR (Vue 2 behaviour unchanged): RefSelector does not forward its own input/hide listeners to the listbox (on Vue 3 they would fall through to the dropdown root), note_agent_actor_line and tooltip_on_truncate call the directive hooks of the running Vue version, plus the spec changes G1–G7.

Splitting strategy

Each row is one future MR, and every commit is green on its own.

• Order. Rows follow the branch order (git log --reverse main..), which is one valid merge order. After the foundation (rows 1–15, needed by every later row), the families can be reviewed in parallel.
• ID. Family prefix and number (F foundation, FS/FG forms, TS tabs, DD dropdown, MD modal, TT tooltip, TB table, PX native Vue 3 portability, X removal).
• Depends on. What a row needs beyond the foundation: shim helpers another family added, or files an earlier commit changed.
• Ship together. MD4 + MD5 (MD4 alone leaves a compat-only portal divergence), TB7 + TB8 (shared changeset wording), TS3 + TS4 (TS3 drops an empty nav-slot <!----> that TS4 restores).
• GitLab first. DD12 needs G2 merged in GitLab first.
• GitLab MR needed? G1–G7 are in gitlab-org/gitlab!264170.

Foundation: utilities out of the vendored tree, version shim, root events, mount helper, Teleport shim (rows 1–15)

#	ID	Commit (future MR)	Files, +/−	Depends on	GitLab MR needed?
1	F1	Lint migrated components for Vue 3 portability 50a2100aa9	1, +98/−0	—	no
2	F2	Move bootstrap-vue spec helpers to tests/__helpers__ eec2eba4b9	26, +75/−68	—	no
3	F3	Remove dead bootstrap-vue config, plugin and locale utilities 27b22d8804	14, +15/−660	—	no
4	F4	Use existing src/utils equivalents inside vendored bootstrap-vue 56025a0a29	21, +21/−294	—	no
5	F5	Move bootstrap-vue DOM helpers to src/utils/dom_utils.js 07b1c224c4	31, +956/−753	F3, F4	no
6	F6	Move BvEvent to src/utils 33b279d36a	10, +262/−131	F5	no
7	F7	Move shared toInteger and key-code helpers to src/utils 406823d1f4	24, +74/−119	F4–F6	no
8	F8	Relocate bootstrap-vue SCSS into src/scss/bootstrap_vue 4b6daec7dc	18, +27/−39	—	no
9	F9	Add Vue 2/3 version shim helpers to vue_utils 26d151886e	8, +984/−46	—	no
10	F10	Add root event bus adapter 66d3aaa1fc	11, +762/−13	F9	no
11	F11	Add programmatic mount helper and use it for GlToast 249acebf14	6, +330/−18	F9, F10	no
12	F12	Add portable transition class helpers and fix GlToast leave class 3419202a50	6, +350/−11	F11	no
13	F13	Replace BVTransporter with a Teleport shim e756c8cda0	9, +650/−341	F9, F11	no
14	F14	Move bootstrap-vue event listener helpers to src/utils 2b015e34ae	32, +277/−216	F5, F10, F13	no
15	F15	Route compat native listeners to the component root in the version shim c1fb3d6c95	2, +345/−16	F9	no

Forms: GlFormSelect and BFormGroup (FS, FG)

#	ID	Commit (future MR)	Files, +/−	Depends on	GitLab MR needed?
16	FS3	Make GlFormSelect portable 7bf0c2fcc3	4, +157/−13	—	no
17	FS4	Delete orphaned vendored form mixins b241ac54a8	8, +5/−212	FS3	no
18	FG1	Inline BFormText and BForm(In)validFeedback into BFormGroup fc73ef576e	16, +230/−830	—	no
19	FG2	Replace BCol and BFormRow with plain elements in BFormGroup 97642cb077	18, +226/−1354	FS4, FG1	no
20	FG3	Rewrite BFormGroup as an internal template SFC f715661771	25, +2010/−2095	FG2	no
53	FG4	Route GlForm and GlFormGroup listeners through the version shim f01687bdba	8, +448/−8	FG3, TB15	no

Tabs (TS)

#	ID	Commit (future MR)	Files, +/−	Depends on	GitLab MR needed?
21	TS1	Add GlTabs and GlTab behaviour specs ported from vendored specs afa0152b3c	2, +1264/−2	—	no
54	TS2	Make GlScrollableTabs listener and attr forwarding portable 5984426178	4, +140/−8	TB15	no
55	TS3	Inline BTabs into GlTabs 518b6e1ed9	9, +1081/−89	TS1, MD5 · ship with TS4	yes: G5
56	TS4	Inline BTab into GlTab 5732eff246	11, +1072/−117	TS3, TB15	yes: G4, G6
57	TS5	Delete vendored bootstrap-vue tabs 34c9de8e83	15, +42/−2849	TS4	no

Dropdown (DD)

#	ID	Commit (future MR)	Files, +/−	Depends on	GitLab MR needed?
22	DD1	Drop dead Vue.extend wrapper from GlDropdown 40fd329038	2, +88/−20	—	no
23	DD2	Delete unused vendored BDropdownGroup 5eb8f29aa4	7, +2/−256	—	no
24	DD3	Inline BDropdownDivider into GlDropdownDivider 4662493c01	10, +250/−107	DD2	no
25	DD4	Inline BDropdownHeader into GlDropdownSectionHeader 5398514f6f	10, +330/−155	DD3	no
26	DD5	Inline BDropdownText into GlDropdownText a35838fde9	10, +314/−136	DD4	no
27	DD6	Inline BDropdownForm and BForm into GlDropdownForm cbf3ed943a	16, +442/−708	FG2, DD5	no
28	DD7	Remove .native listeners on GlDropdownItem in GlFormCombobox d4590294d8	3, +145/−7	—	no
29	DD8	Add public updatePopper method to GlDropdown bd6732968b	3, +97/−0	DD1	adds the API G2 uses
30	DD9	Inline BDropdownItemButton into GlDropdownItem f25d8b9f67	9, +581/−288	DD6	no
58	DD10	Inline BDropdownItem link rendering into GlDropdownItem 39cb315ebe	15, +1086/−343	DD9	no
66	DD11	Port the vendored BDropdown spec onto GlDropdown a32ec12e66	2, +1353/−1178	DD8, DD10	no
70	DD12	Inline BDropdown and its mixins into GlDropdown ac7a785913	17, +871/−1305	DD11, TT6	yes: G2 first
71	DD13	Replace vendored BButton in GlDropdown with native toggle markup dcdd0dfd16	4, +826/−39	DD12	no (API narrowing, no usage)
72	DD14	Remove leftover vendored dropdown files and move dropdown styles 5cb71d1aa6	21, +104/−832	DD13	no

Modal (MD)

#	ID	Commit (future MR)	Files, +/−	Depends on	GitLab MR needed?
31	MD1	Move the modal manager out of vendored bootstrap-vue 11f19e8e92	7, +477/−209	—	no
32	MD2	Route BModal root-bus traffic through the root event adapter f63a911ce4	3, +183/−12	MD1	no
33	MD3	Rewrite v-gl-modal directive without bootstrap-vue 7cf4d3a8b0	9, +626/−363	—	no
34	MD4	Drop scoped-style, attrs-cache and id mixins from BModal a4fb865194	3, +196/−22	MD2 · ship with MD5	no
35	MD5	Rewrite BModal as an internal template SFC 67c1b9753e	23, +3837/−4139	MD3, MD4	yes: G1 (Vue 3 jest)
59	MD6	Make GlModal's template portable fbbbb46a30	7, +442/−30	MD5, TB15	no
60	MD7	Remove leftover vendored modal artifacts ea2e03f57b	22, +326/−1328	MD6	no

Tooltip and popover (TT)

#	ID	Commit (future MR)	Files, +/−	Depends on	GitLab MR needed?
36	TT1	Add GlPopover and GlTooltip characterization specs d6059db982	3, +1880/−1	—	no
37	TT2	Replace tooltip_mixin with open, close, enable and disable methods 54abd7aaac	10, +366/−59	TT1	optional (pure Vue 3)
38	TT3	Extract popper positioning helpers into popper_utils b1827147ca	5, +352/−89	—	no
39	TT4	Extract tooltip and popover DOM helpers into src/utils 527a559d6e	5, +707/−122	—	no
40	TT5	Route tooltip root-bus traffic through the root event adapter 5a9e568a81	3, +254/−14	TT2, TT4	no
41	TT6	Route tooltip target-owner shown auto-hide through the version shim bc0c786796	9, +404/−6	TT5	no
61	TT7	Replace BVPopper and BVTooltipTemplate with a template SFC 0857b993e0	12, +924/−49	TT6, MD5	no
65	TT8	Extract BVTooltip into a portable controller SFC 7bb92ec93e	23, +1215/−956	TT3, TT7	no
73	TT9	Inline BTooltip into GlTooltip 13ee620e3e	12, +900/−70	TT2, TT8	no
74	TT10	Inline VBTooltip into GlTooltipDirective df1023c497	15, +676/−1245	MD3, TT9	pure Vue 3 only (in gitlab MR 264182)
77	TT11	Reimplement GlPopover on the shared tooltip controller 30b7989afc	23, +744/−3672	TT10	no
78	TT12	Remove vendored tooltip leftovers and move tooltip and popover styles a153a8af68	16, +84/−936	TT11	no

Table (TB; TB10–TB14 are spec-only, written against the old implementation)

#	ID	Commit (future MR)	Files, +/−	Depends on	GitLab MR needed?
42	TB1	Delete unused BTableSimple and the vendored table barrel fdb811dd43	8, +25/−658	—	no
43	TB2	Move table DOM helpers and field constants to table_utils 8b6c99fa1e	12, +377/−88	—	no
44	TB3	Move table field and row helpers to table_utils f292aa76f7	24, +585/−337	TB2	no
45	TB4	Move default sort compare to table_utils and use native stable sort 52eafc0301	11, +591/−200	TB3	no
46	TB5	Extract table filtering logic to table_utils 3ad0210e9b	9, +371/−143	TB4	no
47	TB6	Extract table sorting logic to table_utils 5cd63611d4	5, +871/−151	TB5	no
48	TB7	Extract table row selection logic to table_utils 215b8b45d6	7, +674/−82	TB6 · ship with TB8	no
49	TB8	Expose row selection and refresh methods on GlTable 52460b338a	5, +233/−1	TB7	optional (methods instead of $children[0])
50	TB9	Accept items provider functions in GlTable items prop 82bdb62c62	4, +211/−8	TB8	no
51	TB10	Test GlTable pagination, primary key and item formatters directly 9027068160	3, +572/−0	—	no
52	TB15	Make GlTable and GlTableLite slot and listener forwarding portable 5b2a3ee82b	8, +547/−31	TB9	no
62	TB11	Test GlTable filtering directly f6201ec9e8	1, +783/−0	—	no
63	TB12	Test GlTable sorting directly 0c8d08ad58	1, +754/−0	—	no
64	TB13	Test GlTable row selection directly f9dd872a4f	1, +1089/−0	—	no
67	TB14	Test GlTable busy state and items provider directly 39886bf17d	1, +954/−0	—	no
68	TB16	Render table header and footer from a template SFC 9a4b5083b6	18, +1081/−590	TB15, MD5	yes: G3
75	TB17	Render table body rows from a template SFC f5941e7d70	27, +1551/−1233	TB10, TB13, TB16	yes: G7
76	TB18	Move busy, top, bottom and empty rows into the body template f877128f6d	16, +499/−670	TB17	no
79	TB19	Replace BTableLite with a template SFC core and shared table element 83bd39728c	14, +1265/−76	TB18	no
82	TB20	Replace BTable with a template SFC core ff4c14a5b7	27, +1849/−2045	TB11–TB14, TB19	no
83	TB21	Relocate vendored table specs and remove remaining table vendor files 8eecf3b352	47, +3308/−11252	TB20	no

Native Vue 3 portability (PX)

#	ID	Commit (future MR)	Files, +/−	Depends on	GitLab MR needed?
69	PX1	Make specs portable to native Vue 3 4c95e0923b	7, +29/−19	—	no
80	PX2	Forward GlButton listeners through the version shim 9b67bfb696	6, +294/−17	—	no (events declared on native Vue 3 only via nativeEmits())
81	PX3	Declare emitted events that also fall through on Vue 3 6ad591cd29	20, +254/−2	—	no (nativeEmits())

Removal (X)

#	ID	Commit (future MR)	Files, +/−	Depends on	GitLab MR needed?
84	X1	Delete vendored BButton, BButtonClose and BLink f480c77837	14, +8/−2010	MD5, TS3, DD10, DD13	no
85	X2	Remove orphaned vendored utilities and the element-to-instance registry 5fbcb62365	71, +165/−3148	X1, all families	no
86	X3	Remove the vendored bootstrap-vue directory d0d02bf2c5	32, +47/−2525	X2	no
87	PX4	Make the remaining specs portable to native Vue 3 9224b1a3bb	18, +367/−275	X3	no (spec-only)

Consumer follow-ups (GitLab / duo-ui)

gitlab-org/gitlab!264170 (Draft, pipeline:run-all-jest, pipeline:run-all-rspec, pipeline::tier-3): the integration commit plus spec/code fixes. Each fix also passes with the current @gitlab/ui and can land on master before the bump; the exception is the SLA snapshot line of G4.

	GitLab commit	For	Why
G1	Check hidden lazy modals by text instead of empty HTML	MD5	Vue 3 jest lane: VTU 2 serializes the hidden modal's placeholder comment
G2	Use GlDropdown public methods instead of its internal dropdown ref	DD12	Blocking. 4 sites used the private $refs.dropdown. Without the fix, the alert sidebar "Edit" assignee button silently stops opening its menu (no error, no spec). Falls back on releases without updatePopper()
G3	Find GlTable header cells by element instead of component	TB16	header cells are elements now
G4	Check lazy GlTab stubs independently of the prop declaration	TS4	GlTab declares the BTab props, so stubs render lazy="true" / active="true"
G5	Mount real tabs in the DevOps adoption app spec	TS3	GlTabs' own logic now runs in the shallow-mounted spec
G6	Use Vue 2 transition class attribute names in snapshots	TS4	the serializer maps enterfromclass to enterclass, so one snapshot serves both jest lanes
G7	Find GlTable body rows by element instead of component	TB17	body rows are elements now (three AI settings tables, alert management table)

gitlab-org/gitlab!264182 (Draft): the native Vue 3 lanes on the package from !6551. It also carries the GitLab change needed only for pure Vue 3: tooltip_on_truncate.js calls the GlTooltipDirective hooks of the running Vue version (TT10), and the RefSelector and note_agent_actor_line changes above.

Not needed for the bump (before a pure Vue 3 switch):

• TT2. Use open() / close() / enable() / disable() of GlTooltip/GlPopover instead of $refs.x.$emit('open' | …) (tooltips.vue, observability_feedback.vue, ee compliance filters.vue) and add them to the jest mocks. $emit keeps working on Vue 2 and compat.
• TB8. Call selectRow(), …, refresh() on GlTable instead of $children[0] (which still works).

No change needed: GitLab's group_name_and_path_spec finds { name: 'BFormGroup' } and the core keeps that name; duo-ui uses none of the narrowed or removed APIs (DD13 toggle-attrs keys, the bvEventRoot fallback).

design.gitlab.com follow-ups (separate MRs):

• Pre-existing. GlButton, GlFormInput, GlFormTextarea and GlLink pass BSV option names (propagation, immediatePropagation) to stopEvent, which ignores them. GlCollapse binds Vue 2 transition class names.
• Upstream. Tell the author of 39561c88 about its Vue 2 side effects (Known differences).
• After the Vue 3 switch. Delete the Vue 2 Teleport branch and SlotOutlet (native <slot>; also removes the per-cell instance cost on Vue 3: +37% mount / +24% re-render on compat with all 8 GlTable columns slotted). Forward deactivated() of GlTooltip/GlPopover in <keep-alive> to forceHide(). GlPopover renders its slots twice per update on Vue 3. Decide whether GlFormGroup forwards non-native listeners (Vue 2 never delivered them).
• Test infrastructure. Add a real-browser @vue/compat e2e check for nested tooltips and tab panels (jsdom cannot see DOM-anchor and visibility differences).

Known differences

Vue 2 deviations from main

• DD13: GlDropdown toggle-attrs. Keys that named BButton props (href, to, pressed, rel, target) no longer change the toggle; only type applies. event and router-tag render as DOM attributes on link toggles, and a camelCase + kebab-case duplicate renders the kebab one. No GitLab or duo-ui usage.
• TB18: variant in a static tbodyTrAttr object now applies to the busy, top, empty and bottom rows on every render. BSV deleted the key from the object at the first render, so the variant applied only once.
• GlTooltip / GlPopover slot content (TT9, TT11). main (since 39561c88) stops following v-slot content while the tooltip is open and shows comments for comment-only v-slot content. Here, on Vue 2, both follow the slot while open and fall back to the title prop for comment-only content; the title-prop fallback of that commit is kept. A default container set with setGlTooltipDefaultContainer() after mount applies on the next prop, title or content change (GitLab sets it once at boot).

Intended changes visible on Vue 2

The other 20 accepted Vue 2 parity entries:

• Slot presence is checked at render time, so slots added or removed after mount take effect: GlFormGroup label description (FG4), GlModal modal-ok / modal-cancel / modal-footer (MD6), GlTable head slots (TB15).
• An items-provider function no longer logs a prop-type warning (TB9); @input.once on GlTabs runs once (TS3); buttonClass is a declared GlDropdownItem prop, so its junk attribute spelling on link items changes (DD9).
• Other Vue 2 fixes: a thAttr style no longer drops thStyle (TB16); a non-static GlModal destroyed in the update that opens it no longer leaves a copy in document.body (F13); selectAllRows() no longer throws RangeError on very large tables.

Test contracts and snapshots only

• Inlined components declare the BSV props they used to pass on (GlTab, GlTabs, the GlDropdown family, GlTooltip, GlPopover): those keys leave $attrs, and stubs render them as props. Components that now emit events themselves show them in wrapper.emitted() (GlTab, GlTabs, GlDropdownItem links). Components rewritten with declared emits (GlDropdown, tabs, modal and table cores, tooltip, popover, form select) warn on Vue 3 / compat when code $emits an undeclared event on them (no GitLab usage); GlButton and the 14 PX components declare theirs on native Vue 3 only.
• shallowMount of the real GlTooltip renders a comment instead of a stubbed BTooltip; the BTr/BTd/BTh/BTbody components are gone (find rows and cells by element); a hidden lazy GlModal serializes as <!----> under VTU 2.
• HTML only (101 snapshot-only Vue 2 parity scenarios): comment placeholders between table rows and in some slots, style strings in tdAttr / thAttr / tbodyTrAttr serialized like other styles, shifted __BVID__ numbers.

Packaging

• vue-functional-data-merge is no longer a dependency. bootstrap-vue's license notice moved to src/scss/bootstrap_vue/LICENSE (that SCSS still derives from bootstrap-vue). dist/tailwind.css loses 4 utilities only Storybook used.

Compat convergences

581 compat parity scenarios now match Vue 2 (details per changeset):

• .native listeners (also with capture, once, key modifiers) reach the root element of inheritAttrs: false components; listeners added after mount are called; GlTabs shows its empty slot again.
• Transitions use the class prop names of the running Vue, so enterclass / leaveclass no longer leak as attributes; GlToast fades out from show; GlFormSelect change carries the value.
• Toasts, tooltips and popovers mount into the calling app instead of separate data-v-app wrappers; tooltips and popovers are removed right away on destroy and close when a GlDisclosureDropdown or GlCollapsibleListbox opens; the tooltip engine logs no compat deprecation warnings.
• Table rows are focusable and keyboard-handled only with a row-clicked listener, and row listeners are fixed at the first render, as on Vue 2. $on listeners on the internal table do not get row events.

The 43 accepted compat entries are the 20 shared intended changes plus 23 partial convergences: tooltip and popover slot content while open, container forms, the tab link disabled attribute, tab pane transition attributes, an empty foot slot of GlTableLite.

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