Oh, yeah, I added 720p/1080p support and had some back and forth with AboodXD about improving the scaling on the GamePad with a shader. That part never worked out, but the 1080p support works fine. I wouldn't say it qualifies as a continuation, adding 1080p was all I did or know how to do, so the emulator is not otherwise improved in any way. That said, it does build and I included a Dockerfile with instructions in
/ppsspp/tree/wiiu26/WiiU. I've also attached a build to this post since not everybody wants to set up Docker.
I want to be clear that when I say I added native resolution support, I mostly mean that the emulator can now output the original 272p image upscaled to those higher resolutions. Realistically, you can't run PSP games at increased resolutions on the Wii U, so it's purely about the scaling quality boost from not being stuck at 480p. Technically it might be possible to run something at an increased resolution, but that was really never the point. The main attraction is the fact that PPSSPP has a special mode when running at 1080p which does a 4x upscale from 270p. i.e. It crops off a single row of pixels from the top and bottom, and then 270*4 = 1080, so you get a very sharp image on the TV if you disable filtering.