Input issues in Appimage

So I am using Manjaro Linux (5.6.3) and Joplin (1.0.199)

Issue 1 :

When I input Shift + Single quotes key , I expect to get " , But instead I am getting \ , I can’t understand this isuue, because all other application seems to behave fine.

Issue 2:

I use XCompose to insert special character like alpha gamma beta theta and so on, while on all other app except gtk’s one like firefox where I can input only few character and other’s i can’t (idk why). So everything is fine with Kde apps and QT apps where I can insert anything. I noticed Joplin to behave in same fashion where I can’t insert special character but can copy paste into it. Is there a fix for it here? example <Multi_key> <a> <s>
should give me alpha but gives me nothing Multi_key here is RCtrl