Turns out it was somewhat a false alarm. I let the server sit for a day or two and then the theme started working on its own. Not sure what would have prevented it before, or why changes to my theme setting need to sit overnight before taking effect, but I now have your theme working wonderfully

I have the basic Modern theme that was included (I believe), and I tried the Plex theme last night as well

Ubooquity is started up with an init.d script, the same one that is found in the documentation. The command it runs boils down to
nohup java $MEM_OPT -jar Ubooquity.jar --libraryport $UBOOQUITY_PORT --adminport $ADMIN_PORT --remoteadmin --headless </dev/null &>ubooquity.log &

OS is Ubuntu 18.04.3 LTS

My Nginx setup is what I was most concerned about because it relies on some reverse proxies (I believe). I basically convert comics.my-hostname.com to my-hostname.com:my-port and comics.my-hostname.com/admin to my-hostname.com:my-admin-port

When changing themes, I do see the change reflected in the preferences.json file.

And it turns out it's not just your theme. Themes in general don't seem to work for me. I wonder if it's related to my Nginx setup or something else I've done in the past.

I feel pretty dumb. How do I actually install this theme? I downloaded comixology2.zip from GitHub, dropped it in the themes directory of my installation, extracted that directory, and selected it as my theme in the Admin interface. I've restarted my server multiple times and have tried accessing my server in an Incognito Window to make sure nothing is cached, but have yet to see the theme actually activate. I feel like I'm missing a step somewhere. Any help would be appreciated

After digging through some of the JS I found, turns out "No Split" does exactly what I was looking for and shows two pages when there's a two-page spread. Thanks for the great product!

Also giving this a +1. Got Ubooquity set up today and it's exactly what I've been looking for aside from the limit to one page. One page at a time is fine most of the time, but I've been reading Prophet which has some scenes that span across both pages.

Without taking a look at the code it's hard to say, but couldn't you just add a second "container" for a second page that sits right next to the first "container" and then have the "Next Page" button just skip ahead two pages at a time instead of one page at a time? If you get to the end of the list and there's only one page, then only render that page. It would take some minor lookahead logic, but it shouldn't be too terrible. It's hard to judge the difficulty/complexity without seeing how it's all set up currently, though.

Is the code available anywhere online? I'd like to play around with it a bit to see if I can get a second page rendered on the screen.