Low frame-rate after time travel

[ViperAcidZX]

When launching the game and playing as-is it plays fine, but after I time travel, the game's frame-rate is suddenly reduced to ~30 FPS. It only seems to run at the proper speed if I'm in fullscreen but is still affected in windowed mode. This issue is happening with v1.3.0 x64 from the releases page. I never had this issue with the older versions of the decomp, with or without V-sync enabled.