Or, with GUI (and I’ve been saying this many times), you can use a tool like Process Lasso to easily suspend the ffmpeg process (to effectively create a pause). Alsso ideal for 12th and 13th gen CPU owners, so you can (consistently) bind ffmpeg to the P-Cores, and the GUI to the E-Cores, for much improved performance,
None of this detracts one iota from the fact that something as simple as a Pause button should have been present since day 1.