I don't know the lineage of this particular system. But I have worked on janky systems in the past. In one instance, an intern built a language during a summer project. It was an expedient solution to a problem that a team was having, so they began using it. Then they put work into making it faster and integrating it to other systems. Eventually they wrapped a service interface around it and reexported it to other teams. But there were serious semantic problems with the language as a concept and with the technical implementation of the language. Once it had users who came to depend on its bugs, it became very hard to fix, and the whole mess became more convoluted as people tried to build sensible extensions on the rotten core.

It's finally gotten to the point where there is the action potential to fix it in my case, but for a lot of systems with a complex and expedient lineage like this, it never gets there. So garden well, I guess, is the takeaway.

These browser apps are relatively common inside Korean companies. The IE base dates to the pre-crypto-export days, when the Korean government mandated crypto be provided as an ActiveX module. This requires specialized secure input forms within the browser and within-browser error popups, so why not build a within-browser windowing system...

As a user, interfacing with these systems was always hell. Setting up online banking on a new computer would take the better part of a day, and would fail if you didn't have IE security exceptions set, if you were missing Korean font packs, or if your name was too long. And different ActiveX controls installs were required by every webapp. Our company (healthcare) finally rolled out a native Windows app in 2019. It includes its own floating tile manager, and for tasks like viewing PDFs, browser frames are now embedded in a tile...