When I tried Wezterm last year, you couldn't select more than 3-5 lines of text. I went to fix the 'bug', I found that it was intentional because it allocates a string and copies multiple times every time you click and drag.

Even if that's fixed, that design put me off the terminal forever.

I regularly select hundreds of lines in Wezterm. I have never had a problem.

Been using/abusing wezterm for years, my scrollback is set to 1000000 and text selection has never been a problem... copy mode however does make it even easier