Delete key outputs U+007F and U+0621 instead of deleting in PT-BR locale after !263 in certain GNOME apps like Nautilus

I've noticed that after !263 (merged), pressing the delete key no longer deletes the character at the caret as expected. Instead, it now outputs U+007F, and pressing it again produces U+0621.

It appears this issue only occurs in the PT-BR locale and with certain GNOME applications, such as Nautilus, Terminal and Text.

The character in question was introduced in the commit 763f3f93

I found other users experiencing the same problem in this thread: https://bbs.archlinux.org/viewtopic.php?id=298417

While trying to bisect, I found that the problem disappears only before commit 4f554119. However, when bisecting further, the issue reappears in commit c099d010. This inconsistency suggests that some form of caching might be involved, as simply reverting commit 763f3f93 does not resolve the issue, even after a reboot.

It's still unclear why this is happening, it might need to be addressed in GNOME itself. However, since it was introduced with !263 (merged), I'm opening the issue here so we can keep track of it.