Godot: TabContainer children can overflow on tab switch (e.g. Export and Project dialogs)

[saranvdev]

Godot version:
3.1.dev-1

OS/device including version:
Arch Linux

Issue description:
Export manager has too long textboxes: https://i.imgur.com/HvjGhzF.png

Steps to reproduce:
Open export window and enter resources menu.

_Bugsquad edit:_

[vnen]

FYI you can attach images to your issue directly, no need to use an external provider.

[reduz]

No idea why this is going on, but export Window is here:
https://github.com/godotengine/godot/blob/master/editor/project_export.cpp

[nikibobi]

I reproduced the issue. The textboxes get so big because the localization string of their label is larger than the one in english. But in that case the window should also resize, but it doesn't. If I move or resize the window it gets fixed.

While testing this I found a very similar issue with the dialog box saying C# is in beta and again it gets fixed when it is resized.

I am guessing the issue is more general and related to redrawing controls or something. I will try to look for similar issues.

[ghost]

Hey! I'm new here (and in contributing to FOSS too), and I'd like to make this my first bugfix. As I can see, there's no one working on it, so I'd like to give it a try.

[toger5]

I just checked, and i cannot reproduce this on my machine (Linux official 3.0.6)

[ghost]

I was able to reproduce the bug in the export manager once, with polish language, but after dragging the right side of the window, it snapped back to normal, and ever since, even with restarting the application or making a new project or switching between languages, it's been working correctly.

[toger5]

maybe it's an issue with some cached value in the config?
you could still look through the file posted by @reduz. Ill notify you when I'm able to reproduce and under which circumstances.

[ghost]

Alright, I'm gonna go do that.

[ghost]

I have found a reliable way to reproduce the bug: increase the size of the string on this line in project_export.cpp (around line 962)

resources_vb->add_margin_child(TTR("Filters to export non-resource files (comma separated, e.g: *.json, *.txt)"), include_filters);

If you increase it with at least a couple of characters, the box will be messed up, but will adjust back if you resize the window, move the window, or exit from the window and reopen it. As @nikibobi mentioned this must be a more general issue, I think too.

[toger5]

could be the min_size function that is broken