Assignment: Insert freqeuntly used comment throws error

by Matthias Giger.  

In an assignment where students have to upload a PDF, we try to use the option "Advanced grading - Marking guide", because the "Frequently used comments" will save teachers a lot of work (grading of 100+ students).

The comments itself are written in German, which means they include some special characters.

When trying to assess an assignment the system throws an error as soon as you press the "insert frequently used comments" button:

{"error":"Coding error detected, it must be fixed by a programmer: Invalid json in request: Syntax error","stacktrace":null,"debuginfo":null,"reproductionlink":null}

You can go back to the grading page, but all the input will be lost. At the moment all I can do is to tell fellow teachers not to touch that button.

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