OK, it looks like the affected part of the code is precisely what got changed in the latest sunshine-external commits, which will all be part of v1.26.7.11. I guess you should now wait for the latter to be released (perhaps tomorrow, or on Saturday).
However, it would be cool if we could compare v1.27.6.10 and v1.26.7.11: could you please IM me in world when you are there, and I'll TP to you, at which point we could try and walk our avatars side by side and see if I crash too when you do ?...