I bypassed the Dark mode limitation, at least while reading, by using KOreader. This little ereader allows to bind settings toggle and other utilities to taps in the corners, thus I toggle the Dark mode by a single tab. I can not recommend KOreader enough for a Boox tablet, Neoreader is good but KOreader is on another level completely. Also way faster than anything else I’ve tried. It may have a steep learning curve but it’s 100% worth it.
Preach bro