fix: guard against None/empty input in clean_dangerous_html - #662
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arbirali
approved these changes
Jul 31, 2026
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Problem
Course about page (/about) throws a 500 error when the course overview
is None or whitespace-only.
clean_dangerous_htmlpasses the valuedirectly to lxml, which returns None for empty input, causing:
AttributeError: 'NoneType' object has no attribute 'getroottree'
Fix
Updated the null check in
clean_dangerous_html(markup.py) to alsocatch whitespace-only strings, and return
HTML('')instead of theraw None to stay consistent with the function's return type.
Changes
openedx/core/djangolib/markup.py— addedhtml.strip()check and fixed return valueNote: this issue was previously fixed in #615 but the fix was not ported over to develop when upgrading.