Some browser basics first. Most browsers have a backend and a frontend. Mozilla for example uses Gecko and the SpiderMonkey JS engine, with Gecko doing the all the rendering stuff. We use Gecko 45 in our Mozilla apps. The front end with Mozilla is Firefox, also SeaMonkey and Thunderbird, all using the same rendering engine and JavaScript engine. Web pages look basically the same whether viewed in FF, SM or even TB. SM and TB also use MailNews, another backend.
So the frontend is basically the UI. To be portable, the frontend uses OS specific widgets to draw the graphical stuff. Mozilla has widgets for each OS it supports to look native. Mozilla's license is MPL, similar to GPL or LGPL. The backend is usually more portable, though now a days uses some advanced OS stuff.
Chromium is BSD licensed with the source available. Chrome adds a bunch of closed source Google stuff. Chrome/Chromium is the frontend, the backend is Blink and the V8 JavaScript engine. There are a lot of browsers that use Blink and are usually considered Chrome based. This includes our Dooble port.
The problem with Chrome is the widget set. In open source there are 2 main widget sets, GTK, currently usually GTK3 and Qt, mostly Qt6 today.. Chrome and most of the other browsers based on the same backend uses GTK3, which we do not have a port of and porting it would take a lot of time and energy by a knowledgeable developer or team. So most of these Chrome based browsers are not going to work.
The Qt people have ported the backend and some of the Widgets to Qt, latest to Qt6, which also has the SimpleBrowser as a proof of concept. We do have the Qt widget set thanks to years of work by Bitwise, with current work on Qt6 being done by Paul. Wasn't that many changes between Qt5 and Qt6.
So basically most Chrome based browsers including Supermium would need GTK ported to OS/2, a huge job and is not going to happen without a lottery win or such.
We can use the same backend with Qt based browsers, we're doing it with Dooble, which sadly seems the only Qt based browser being worked on. And it only has one developer behind it. The frontend works great on OS/2 but we still need more work on the widgets, drag'n'drop for example needs to be implemented.
Bitwise, and now Paul have also done work on porting the backend but we've run into limits of our OS, including being 32 bit. Until someone very knowledgeable, like dmik of Bitwise can figure out how to proceed, we're stuck.
Another advantage these Win32 browsers have is they can be built on a 64 bit system. We don't have that option, which is one of the big problems, lack of address space for building.