1.18.0 changing "sync to exact content ramerate" ON/OFF causes the screen to flicker for a moment

[Tasosgemah]

I'm not sure if this is an issue or the expected behavior.

In any previous RetroArch version, changing this to ON/OFF while in the menu was just like any other toggle and didn't cause the frontend to flicker (Turing the screen OFF for half a second).

Doing the same action while in-game using the hotkey doesn't cause the screen to flicker though.

So something changed but i can't tell if it's for the best or there's a bug. The feature works fine otherwise, the games run smoothly on my 240hz screen. The only issue now really is that now looks more janky when you fiddle with the ON/OFF switch.

[Tasosgemah]

I assumed the flicker happens because something major is changing with the video. But the feature also works when flipping using the hotkey (yes there is a hotkey for this) but this way it doesn't cause any flicker. So i did more testing with GenesisPlusGX and Sonic, to see if i'm missing something.

• Starting RetroArch with the feature OFF: The games stutter a bit and if i use the hotkey they smooth out. Pressing the hotkey once more, the games stutter again. So it works as intended.
• Starting RetroArch with the feature ON: The games run smooth and if i press the hotkey i can see the stutters. Pressing it again, the motion smooths out. Again, works as intended.

So the hotkey works fine like before without any flickering when tapping it to change states. So why does the screen flicker like that when you toggle the feature from the menu switch?

[Ophidon]

I recently added sync to exact content framerate to the list of the synchronization features that request a reinitialization, is why that happens from the menu. When it's not done, it can have frame pacing issues switching between some of the sync methods (higher swap intervals/bfi/subframes/sync to exact) until a full RA restart. And framepacing issues are -super- bad when using BFI. Safer to just do it universally for something that 'normally' wont be being switched between on/off except rarely.

So, if anything, the bug is that it should be changed to cause that flicker via the hotkey too. ;)