Answer by Dmitry Melnikov for Compose key sequence for 'almost equal to' U2248 character stopped working in Fedora 37

This is IBus ignoring your /usr/share/X11/locale/en_US.UTF-8/Compose file.

You can re-define combinations directly in your ~/.XCompose file.I used file from https://github.com/kragen/xcompose/blob/master/dotXComposeIt contains many combinations, including Compose~~ as ≈