Add tooltips to the UI

[rene-coty]

Most of the buttons lack 'tooltips' to indicate what they trigger, which makes understanding the app's features (sometimes) not evident… E.g. I was confused by the button that allows importing from Quizlet/Anki, thinking it created a backup of my Flashcards set; same for the 'export' button next to the 'delete' one 😅

[david-swift]

Thanks for reporting that, I'll add a tooltip to every icon-only button. What icons do you think would communicate the import/export features better?

For importing, I found the following two icons that could be more suitable:

This one feels less suitable, but it may be an option as well:

In Errands, the following icon is used for exporting:

Maybe, the "copy" icon works as well since exporting is about copying a set's content:

What do you think about those icons? Which one do you prefer, or do you think there's another one I should consider?

[rene-coty]

Thanks for your reply! The export icon in itself seems pretty good to me, I was especially confused by the import icon. Your first proposition (the arrow-into-box symbolic) looks very adequate though.

[david-swift]

I fixed this in the commit 72fae89. Thanks again for opening the issue!