Touch screen page jumping and disabling GTK's built-in inertial scroll makes it hard to use for some users.

[latenightdef]

Affects versions :

• OS: Fedora 37
• (Linux only) Desktop environment: Gnome-Wayland
• Which version of libgtk do you use: 3.24.26
• Version of Xournal++: 1.1.3 2dbd16d2
• Installation method: Flatpak from Flathub

Describe the bug Similar to #4597 and #4486 , swiping through pages with touchscreen makes it sometimes even jump from page 7 to the top of the first page on a small 10-page PDF file. Disabling GTK's built-in inertial scroll functionality makes the page stop jumping, but also makes it much more difficult when we need to scroll across many pages when zoomed in, such as when looking at lecture PDFs on devices with a smaller touchscreen. We need another way to handle this.

To Reproduce Steps to reproduce the behavior:

1. Open a PDF file
2. Disable GTK's built-in inertial scroll functionality
3. Try to scroll through multiple pages, or in the same page while zoomed in, without using the page number button

Expected behavior Inertial scroll works correctly

Additional context This will help users migrated from other popular handwritten note-taking apps on iOS/Android tablets

[major-mayer]

I can confirm that this is still an issue in Xournal++ 1.2.2. Is there any fix for the GTK inertial scrolling expected in the future?