Steps to reproduce:
- Setup a custom filter with a big number of tags. The ones I currently have for testing is
I do not think the "Sorted by" makes a difference here but I have "Newest" selected.
I also do not think the "Filter by" makes a difference. I chose none of the options.
For completeness, I have called it "test" but I do not think the name matters.
Note that the zzzz tag does not exist. I use it for padding.
- Open the custom filter from the side bar. This works and you get questions filtered by the given criteria. Live reloading also works fine - you get notification for new questions and clicking it loads them:
- Refresh the page.
Expected result: everything works like going at step 2 again - questions are loaded and filtered.
Actual result: An error page shows up with the following text:
Bad Request - Invalid URL
HTTP Error 400. The request URL is invalid.
Firefox 89.0.2 on Windows 10
Chrome 89.0.4389.90 on Windows 10
Firefox 89 on Manjaro Linux
Chromium 90.0.4430.212 on Manjaro Linux
wget and curl on Manjaro Linux
Brave 1.26.74, Chromium 91.0.4472.124 on Android
Firefox 89.1.1 on Android
Happens both on my normal landline as well as a separate mobile network.
Long filters used to work yesterday. I have a filter I use daily and only noticed the problem this morning (2021-07-15) around 05:00 UTC.
The failure seems closely related to the tag filter. Removing an or operator can also produce a working link, however, the filtering expression is now different (no "or" means an implicit "and").
It is most definitely not the amount of tags involved, it is the literal length of the filter string. Adding a tag like
will auto expand to
[ecmascript-6] or [ecmascript-5] or [ecmascript-2016] or [ecmascript-next] or [ecmascript-2017] or [ecmascript-harmony] or [ecmascript-2020] or [ecmascript-3] or [ecmascript-intl] or [ecmascript-2018] or [ecmascript-4] or [ecmascript-2021] or [ecmascript-2019]
It seems like the problem is around 262 characters of a filter string in the URL:
Working (261 characters):
Not working (262 characters and above):