I forgot to mention that I was verifying with samplerate: 96000 Hz and Buffer size: 1024 samples.
Also, I found a way to reliably crash REAPER from a new project using _mini_crush.jsfx.
samplerate: 96000 Hz | Buffer size: 1024 samples.
1: Load _mini_crush.jsfx
2: Set Chain oversampling to Oversample up to 705.6k/768k
3: Set Chain PDC Mode to Per-FX compensation (classic REAPER 1.0-6.19)
4: Set PDC to 1 in _mini_crush.jsfx
5: Press play button
6: Close the project
This method does not crash when Oversample up to 176.4k/192k, but crashes when Oversample up to 352.8k/384k and Oversample up to 705.6k/768k. (samplerate: 96000 Hz | Buffer size: 1024 samples)
As additional information, I restarted windows and it was still broken.
Windows 10 Home | REAPER v6.78+dev0404/win64
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