I’ve seen the thing about ‘mixed refresh rate monitors’ couple of times and I also don’t get it. What issues are people having?
If you use multiple monitors, X treats them as one big monitor. And it will refresh that one big monitor at only one refresh rate, usually the slower one.
Say you have a 144hz monitor and a 60hz monitor. X will choose to refresh that one big monitor at only 60hz. So if you drag windows around on your 144hz, it will visually look like 60hz.
There are some exceptions to this. The cursor will move at the highest refresh rate if it’s operating in hardware cursor mode. In software cursor mode, it will look laggy. Games will usually operate at the higher refresh rate.
fractional scales are an issue for them?
This is a whole other issue. Not everything implements fractional scaling nicely. For example, currently GTK handles fractional scaling by rendering at 200% scaling, then resizing the output. This uses more more processing power and uses more battery. And things are fuzzy. As for why, imagine you have a 15 pixel wide element at 100%. With fractional scaling at 125%, that element is then supposed to be 18.75 pixels wide, which is impossible. So what do you do? Round up? Round down? Same question for a 17 pixel wide element, at 125%, it would be 21.25 pixels wide. Round down? Round up?
Some toolkits don’t do the render at 200% then resizes method, but still suffer from other issues.
As for focus and positioning both Gnome and Awesome have settings for this and I never had issues with any of it.
Most stuff follows the rules, but not everything. Discord, Steam, and Bitwarden ignore my settings under X. But I can force Discord and Bitwarden to run using Wayland, which fixes the issue.