Wincompose does not work in Pidgin
Windows 10 20H2 Pidgin 2.14.4 (but also in previous 2.14 versions). Did also Pidgin reinstall with gtk+ reinstall. Wincompose 0.9.7 (also 0.9.8) I have Caps Lock as compose key, but tried setting Scroll Lock as alternative and did not work with it also) Caps Lock a " results ä in other programs, but nothing appears in Pidgin. It works fine in in HexChat, which is also using gtk+ (but appears to be using newer version)
This happens to be a problem with Pidgin not understanding VK_PACKET messages, which are sent by WinCompose. Here is another person with the problem, for instance.
The PhraseExpress software appears affected, too, and offers the user the ability to use Sendkey instead of VK_PACKET. I do not like that very much because it tends to cause more problems, but I will find a way to detect Pidgin windows explicitly and use Sendkey only in that case.
Ok, now that I know correct terms I managed to find some issues about US-International with gtk... And testing manually upgrading gtk+ to version used in gimp made WinCompose work in Pidgin. So it is issue of old gdk+ version. So it is probably pointless to add any workarounds to WinCompose. Taking it over to Pidgin side.
Yes, if the Pidgin devs could make a new release with newer GDK libraries that would be great!
Created https://issues.imfreedom.org/issue/PIDGIN-17527 which links another issue, that documents workaround (which is not perfect, but appears to be working currently).