Thanks to the pandemic, I'm been spending a lot of time on Zoom lately, and I'm grateful to have it. The Zoom Linux client seems to be almost as good as the other clients. The only thing that I know is missing is virtual backgrounds, which I do not particularly miss.
That said, I did run into one minor bug (I think). It has to do with what I think is called the "panel". (I've found it strangely hard to confirm this, despite a good bit of searching.) What I'm referring to is a widget that sits off to one side (and can be moved by me) when Zoom is running full screen and a presenter is holding the "spotlight" (owning the bulk of the window). The panel has four buttons at the top that let me choose its configuration. Three of them will show just my video (small, medium or large). The fourth one will show a stack of four videos, each a participant (excluding the presenter), with mine first and the other three selected by some rule I cannot fathom. (Empirical evidence suggests it is not selecting the three best looking participants.) Showing my camera image isn't exactly critical, but it's somewhat reassuring (meaning I know my camera is still working, and I'm in its field of view).
I'm running Zoom on both a desktop and a laptop, the latter exclusively for online taekwondo classes. On my desktop, the panel behaves as one would expect. On my laptop, however, the panel window assigned to my camera was intermittently blanking out. Randomly moving the cursor around would bring the image back (temporarily). This happened regardless of what panel configuration or size I chose.
On a hunch, I disabled the screen lock option on the laptop (which would normally blank the screen or show a lock screen if the laptop sat idle for too long. To be the clear, even with no keyboard/mouse input from me, the laptop was not showing the lock screen or sleeping -- the main presenter was never interrupted. It was just my camera feed that seemed to be napping. That said, disabling the lock screen seems to have helped somewhat. If the panel is showing only my camera, it still blanks after some amount of "idle" time; but if the panel is set to show a stack of four cameras (including mine), mine does not seem to blank out any more.
It's still a mystery to me why mine blanks when it's the only one in the panel, although it's clear there's a connection to my not providing any keyboard or mouse input for a while. The blanking never happens on my desktop. They're both running Linux Mint (the laptop having a somewhat newer version), and they're both running the latest version of the Zoom client. The laptop has a built-in camera whereas the desktop has a USB webcam. The desktop, unsurprisingly, has a faster processor, and probably better graphics. My typical desktop Zoom usage does not involve extended periods of inactivity on my part (if I'm not doing something useful as part of the call, I'm surreptitiously checking email or playing Minesweeper), so the lack of blanking on the laptop may just be lack of opportunity. It might be a matter of the desktop having better hardware. It might just be some minor computer deity figuring it's more entertaining to annoy me during a workout than during a meeting. Anyway, turning off the screensaver got rid of at least part of the problem. If anyone knows the real reason and/or the right fix, please leave a comment.