UI/Qt: Add customisable scrolling speed & invert scroll directions

[Jaycadox]

Adds:

• Edit > Settings > Scrolling Speed
• Edit > Settings > Invert Vertical Scrolling
• Edit > Settings > Invert Horizontal Scrolling

Which allows the user to specify whether they would like inverted or non-inverted scrolling for each direction, as well as specifying the generic scroll speed multiplier.

[shlyakpavel]

I see no reason why should this be a browser feature, rather than environment/system configuration

[Jaycadox]

I see no reason why should this be a browser feature, rather than environment/system configuration

In my specific case, Ladybird doesn't follow the correct behavior by default regarding horizontal scrolling, as it is inverted compared to other apps. Vertical scrolling is natural but horizontal isn't, whereas on Firefox and Chrome, both directions are natural.

I also personally find it useful for apps to have scroll speed settings, as whether it is DPI scaling, or different behavior between apps, getting apps to share the same scroll speed isn't guaranteed by default.

The feature is also entirely opt-in and changes no default behavior.

[gmta]

Agreed with @shlyakpavel here - Ladybird should do the right thing by default as well. The platform dictates how scrolling works.

[Jaycadox]

My argument here is that the environment might not consistently handle scrolling through window scaling (or that different apps might use different methods of reading scroll input, which through edge-cases like scaling might result in different scroll speeds). And as such, it would be nice to be able to correct for this in Ladybird.

And regarding inverting the scroll directions: as I am having an issue relating to horizontal scrolling being in the wrong direction compared to any other app, would you instead believe that it would be better to fix that underlying specific issue, versus a solution that would allow a user to specify desired behavior?

I can totally understand the argument for Windows and MacOS desktops, but feel specifically for Linux and the larger amount of configurations (X11, Wayland, XWayland), and desktop environments/window managers, inconsistent behavior is basically inevitable.

[gmta]

Yes, we should definitely do the right thing first by default. Only then should we consider making it possible to change the default behavior, but let's discuss that first since there are many ways that could take shape.