The cheap LCD will probably not be able to produce enough light to brighten up the main display, and if the two panels are not of equal size, you will need to add some depth to the unit and come up with a projection system to "blow up" the light map to cover the entire image.
At my company we are using dockerized mailcow on a Hetzner VPS and it has taken us some time to have the IP whitelisted in all major e-mail providers.
The easiest to work with have been Microsoft and Yahoo. I still haven't found a way to whitelist our IP on centurylink.net, charter.net and att.com (please let me know if you have any ideas)
With NVDA on Windows, when I read the comment normally, it's spelled out. When I read it character by character, I get "symbol FFF8" for each of the hidden Unicode characters. And when I move line by line through NVDA's linear representation of the web page, the hidden characters count against the length of the line for the purpose of word wrapping.
Narrator's behavior is weirder. If I turn on scan mode and move onto the line with the up or down arrow key, Narrator says nothing. If I read the current line with Insert+Up Arrow, Narrator spells it out like NVDA does. When moving character by character, Narrator says nothing for the hidden Unicode characters. And because Narrator doesn't do its own line wrapping but defers to the application to determine what counts as a line, the text only counts as one line.
Disclosure: I used to work on the Windows accessibility team at Microsoft, on Narrator among other things.
Taking screenshots/streaming is not a hard problem. However Wayland artificially turns something as simple as taking a screenshot into a hard problem what was before a simple function call to XGetImage(). As exercise I recommend to implement a native screenshot application in both X11 and Wayland.
How easy would be to place a cheap LCD at the back of the main screen and mirror the same output (in horizontally inverted mode)?
Technically it might require synchronizing the frame latency differences between the two devices, but would such a hack improve the perceived quality?