it’s not really a good idea to install Buster packages on Bullseye. As you can see, this might lead to bigger issues and conflicts.
This issue has been resolved in the latest update?
Updating the Chromium package is out of our scope. We use the version available on global Debian apt source.
Sadly there was no update since March and I didn’t get further reply on the Debian bug tracker. I’ll retest and in case give the bug report some bump.