Appimage crash on open in Fedora 31, Arch (with variable fonts)

Steps to reproduce:

• Download AppImage from Inkscape website (Inkscape-fe3e306-x86_64.AppImage)
• Run $ chmod u+x Inkscape-fe3e306-x86_64.AppImage

What happened?

Gnome dialogue pops up with unreadable characters.

Console shows the following output:

$ ./Inkscape-fe3e306-x86_64.AppImage
Run experimental bundle that bundles everything
Gtk-Message: 11:46:51.678: Failed to load module "canberra-gtk-module"
Gtk-Message: 11:46:51.681: Failed to load module "canberra-gtk-module"
Pango version: 1.42.3
Fontconfig warning: "/etc/fonts/conf.d/10-hinting-slight.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/10-hinting-slight.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/10-hinting-slight.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/40-nonlatin.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/40-nonlatin.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/40-nonlatin.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/40-nonlatin.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/40-nonlatin.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/40-nonlatin.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/40-nonlatin.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/45-generic.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/45-generic.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/45-generic.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/45-generic.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/45-generic.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/45-generic.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/45-generic.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/45-latin.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/45-latin.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/45-latin.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/45-latin.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/45-latin.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/45-latin.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/45-latin.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/49-sansserif.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/49-sansserif.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/49-sansserif.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/49-sansserif.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/49-sansserif.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/49-sansserif.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/49-sansserif.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/50-user.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/50-user.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/50-user.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/50-user.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/50-user.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/50-user.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/50-user.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/51-local.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/51-local.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/51-local.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/51-local.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/51-local.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/51-local.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/51-local.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/60-generic.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/60-generic.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/60-generic.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/60-generic.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/60-generic.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/60-generic.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/60-generic.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/60-latin.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/60-latin.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/60-latin.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/60-latin.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/60-latin.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/60-latin.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/60-latin.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/65-fonts-persian.conf", line 34: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/65-fonts-persian.conf", line 35: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/65-fonts-persian.conf", line 35: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/65-fonts-persian.conf", line 35: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/65-fonts-persian.conf", line 36: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/65-fonts-persian.conf", line 36: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/65-nonlatin.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/65-nonlatin.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/65-nonlatin.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/65-nonlatin.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/65-nonlatin.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/65-nonlatin.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/65-nonlatin.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/69-unifont.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/69-unifont.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/69-unifont.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/69-unifont.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/69-unifont.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/69-unifont.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/80-delicious.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/80-delicious.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/80-delicious.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/80-delicious.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/80-delicious.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/80-delicious.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/90-synthetic.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/90-synthetic.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/90-synthetic.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/90-synthetic.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/90-synthetic.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/90-synthetic.conf", line 6: invalid attribute 'version'

** (ld-linux-x86-64.so.2:40757): WARNING **: 11:46:52.363: Fonts dir '~/.config/inkscape/fonts' does not exist and will be ignored.
Fontconfig warning: FcPattern object weight does not accept value [40 210)

Emergency save activated!
Emergency save completed. Inkscape will close now.
If you can reproduce this crash, please file a bug at https://inkscape.org/report
with a detailed description of the steps leading to the crash, so we can fix it.
Gtk-Message: 11:46:52.684: GtkDialog mapped without a transient parent. This is discouraged.

(ld-linux-x86-64.so.2:40757): GLib-GObject-WARNING **: 11:46:52.689: invalid cast from 'GtkBox' to 'GtkToolbar'
Can't get snap toolbar
[1]    40757 segmentation fault (core dumped)  ./Inkscape-fe3e306-x86_64.AppImage

What should have happened?

Program launches as expected.

Inkscape Version and Operating System:

• Inkscape Version: Inkscape v1.0 beta1
• Operating System: Arch Linux with Gnome DE