This looks a bit similar to previous issues such as https://github.com/microsoft/pxt-arcade/issues/1855 and https://github.com/microsoft/pxt-arcade/issues/702, is there any current known bug that could trigger this? I’m using the live version, and it’s possible that I had never opened the Blocks view while working on it previously until I closed the editor.
Separately, is there any way to recover the lost source code? I was poking around a bit in Chrome Dev Tools in Application / Storage, and I found the IndexedDB storage (_pouch_pxt-arcade / by-sequence (go to last page), but that also has the empty main.ts.
I still have UF2 files, and https://github.com/microsoft/uf2#embedding-sources mentions that the file format supports embedding sources - does Arcade do that, and if yes is there a tool to extract it?
Note to self: make sure to export or save as image regularly, I was trusting the editor to keep my work-in-progress safe…