Raw error output:
Problem while applying patch in revision 209784:
hg error in cmd: hg import --no-commit -s 95 /tmp/tmpn626t6la: applying /tmp/tmpn626t6la
patching file toolkit/modules/RemotePageAccessManager.sys.mjs
Hunk #1 FAILED at 100
1 out of 1 hunks FAILED -- saving rejects to file toolkit/modules/RemotePageAccessManager.sys.mjs.rej
abort: patch failed to apply