Special Characters menu opens but won't insert character

I found out that I am able to insert emojis if I use the full-fixed character viewer, no difference between single or double click. However, if I choose to use the simpler, pop-up menu that regularly opens with the keyboard shortcuts (either Edit > Emoji & Symbols or FN key or CMD + CONTROL + SPACE), it won't work (wether single or double click).

This one doesn't work at all:

But this one works:

Any ideas on how I can fix the simpler pop-up menu without having to open the fixed character viewer (which needs to be manually closed after character insertion)?

Thanks!

It also works with either double or single click for the full Character Viewer panel and also the smaller, but fixed, panel (the one you have to close with a click on the x, as below):

But it won't work at all for the pop-up menu (the one in which you're supposed to single click the emoji and it gets inserted + the panel automatically disappears), as below:

I have tried a multitude of apps such as Text Edit, Notes, Safari, Keynote and really anything that will let me type text into. Same behaviour in all of them.

Thanks for the suggestion, didn't work though, double click is not the issues. Seems to really be some sort of bug.

Thanks for the suggestion, unfortunately no change.