AttributeError: 'Request' object has no attribute 'is_xhr'

[matt-bernstein]

Got this error while trying to view or edit any image in the browser. The root cause is in flask - see discussion here.

The fix, as described in that thread, is to pin Werkzeug to an older version from before this function was deprecated. Add the following line to requirements.txt before installing:

werkzeug==0.16.1

[AlexandrParkhomenko]

see
need patch

request.headers.get("X-Requested-With") == "XMLHttpRequest"