It's a 30fps game, so as long as it doesn't have dropped frames or is recorded at some weird framerate like 20 or 29.97, it's just a matter of loading it in a video editor and going to the start and end frame (in-depth explanation: https://www.speedrun.com/Speedrunning/thread/u2alf - it looks more complicated there because you don't need half the stuff, if you only time your own runs). But I retime all submitted runs anyway. It only takes like half a minute most of the time.
@I_o_I i was recording at 30fps, but rerendering at 29,833 (wtf) i changed that for the future
I added an ingame timer to the game (with help from @dimusnail).
With this your PC's performance no longer affects your time and the annoying retiming is eliminated.
Also I found out that the game does not actually run at 30 frames
