From Lua, if time selection end is set to a value greater than 301694800961371615 (yes it's precise haha) you can observe visual glitch while scrolling.
Code:
reaper.GetSet_LoopTimeRange2(0, true, false, 10, 301694800961371615, false) -- Works
reaper.GetSet_LoopTimeRange2(0, true, false, 10, 301694800961371616, false) -- Glitch
PS: what is special about 301694800961371615? I tried to google it, but there are no results
Edit: (I'm using OSX 12.3 and reaper 6.59)