Blurred objects clipped by groups don't render correctly

Summary:

If an object...

• has a nonzero blur, and
• has a clip mask which is a group of clones

then, when viewing the object in Inkscape, parts of it frequently disappear, as if some of the grouped clones don't exist.

Steps to reproduce:

• open Inkscape
• draw two objects
• draw a third object, change its blur, and maybe its opacity (not sure this is required)
• select the first two objects and clone them
• select the clones and group them
• make the group a clip for the blurred object
• zoom in and out

What happened?

The blurred object appears over only one of the two other objects sometimes. This is not consistent, but changing the zoom level a few times should trigger it.

This only happens when filters are enabled, and doesn't affect exported PNGs.

What should have happened?

The blurred object should appear over both of the other objects at all times.

Sample attachments:

Example document: Example document

Correct render	Incorrect render

Version Info:

- Inkscape Version: Inkscape 1.2-dev (9a1a09f7b1, 2021-05-12) (has existed since 1.0)
- Operating System: Artix x64
- Operating System version: N/A

This might seem obscure, but I use this feature a lot, so it's very annoying for me!