Using container.NewThemeOverride leaks memory until window closing

[dweymouth]

Checklist

• I have searched the issue tracker for open issues that relate to the same problem, before opening a new one.
• This issue only relates to a single bug. I will open new issues for any other problems.

Describe the bug

When adding a widget to a container.NewThemeOverride, the widget and its override theme are stored in the overrides map. This is never cleaned out except when a window is closing. This is because the deletion of the widget's entry in the overrides map happens in cache.DestroyRenderer, but that function is only called when a window is closing. Elsewhere (eg in the regular clean task), renderers are directly destroyed instead of by calling this function, which misses the deletion of the entry from the overrides map, if that widget had a theme override.

How to reproduce

just check the code as described above. Or create an app that cycles through new widgets, applying an override to them, and then not using them. It will leak memory

Screenshots

No response

Example code

n/a

Fyne version

2.5.0

Go compiler version

n/a

Operating system and version

n/a

Additional Information

No response

[Jacalz]

I would potentially consider this a release blocker

[dweymouth]

I would potentially consider this a release blocker

Well we already released... but I have a PR for the fix. It is not a big leak in most apps since I imagine most don't create and discard a lot of widgets with overridden themes. We've had much worse leaks in releases before that no one (except me) complained about ;) e.g. when we were leaking every image.Image that had ever been rendered in a canvas.Image

[Jacalz]

Well we already released...

I know we released 2.5.0, I was talking about the first bug fix release.

[dweymouth]

Well we already released...

I know we released 2.5.0, I was talking about the first bug fix release.

Ah, yeah makes sense, I'll add the blocker label

[andydotxyz]

This looks to be fixed then :)