perf: Speed Up Opening of Settings Dialog

[Nerixyz]

Pull request checklist:

• CHANGELOG.md was updated, if applicable

Description

I noticed that opening the settings dialog is really slow.

Two things jump out:

1. A lot of time is spent inside updateScale.
2. Calling setWindowFlags results in style recalculations (Before, After).

I'm not sure if my fix to reduce calls to updateScale is correct. It would be nice if people could test this (e.g. with different zoom-levels and on high-dpi). If my fix turns out incorrect, I'd like to add a comment in the code as to why the change-callback must be run when creating the window (the second call to updateScale as added in d796517 to fix #1266).

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[kornes]

There is also this call

chatterino2/src/widgets/BaseWindow.cpp

Line 787 in f2b35fb

this->updateScale();

triggered a LOT by WM_SHOWWINDOW, at minimum it could be changed to check if nativeScale_ actually changed, but it could be also dropped from here i think, because WM_DPICHANGED handler is already calling updateScale()

another pr should properly fix #1266 without this double scalling fuckery :D

[pajlada]

Just changelog entry rewording, other than that the changes are solid 👍
thank you

[Nerixyz]

triggered a LOT by WM_SHOWWINDOW

I noticed that as well. I changed it to only call updateScale if the scale actually changed when this event is dispatched. This requires some further testing.

[Nerixyz]

triggered a LOT by WM_SHOWWINDOW

I noticed that as well.

but it could be also dropped from here i think, because WM_DPICHANGED handler is already calling updateScale()

Probably, though, maybe WM_DPICHANGED doesn't get fired in some instances?

another pr should properly fix #1266 without this double scalling fuckery :D

True, I think there might be more low-hanging fruits.

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[kornes]

Probably, though, maybe WM_DPICHANGED doesn't get fired in some instances?

WM_DPICHANGED covers moving between screens and current screen change, so im 80% sure it could be removed from here, but i would leave it, once chatterino upgrades to qt6 it can be revisited with new dpi oriented apis

PR looks good to me 👍

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"