Source Diff makes the right side read only because it reflows it to match the file on the left.
Thanks - I finally had figured that out. I've turned that option off. (as an aside, if I turn Source Diff on from the the "Options..." button in Diffzilla, then click OK on the "re-diff?" dialog, neither of the files gets marked read-only).
If the buffer open? If so, is the buffer read only to start with? Sorry, but I have to ask.
No need to be sorry - it's a fair question. As far as I know, the buffers being diffed were never marked read only to begin with (I just noticed that the changed to read only in the SE editor while the diff is active). The buffers involved in the diff were always open in SE.
I cannot reproduce the problem where both sides of the diff ended up being read only. If it happens again I'll ask again - unless I can figure it out on my own. But as of now you can close/drop this.
Thanks