Truncated / incomplete capture on Perplexity and ChatGPT-type AI chat windows

When attempting to save long chat windows from Perplexity or ChatGPT, the resulting saved page is truncated way before the end is reached, so only perhaps 5% has text while the rest is all blank (not shown in attached screenshot, which shows only the beginning of the blank part).

In other words, the whole chat is saved, but only perhaps 5% of the beginning has text while the rest is blank. I have saved other scrolling-type pages before as long as this and typically Singlefilez is successful. Somehow the AI chat windows break Singlefilez.

Singlefilez version 1.22.79 with Firefox Version 140.0beta

Screenshot (red outlined area denotes beginning of blank area which extends to the end):