When attempting to enable a BetaFeature (e.g. TwoColConflict) from the user's preferences panel upon clicking save the page reloads with the once selected BetaFeature now deselected and still disabled.
This phenomenon can be seen here during selenium tests for TwoColConflict: https://integration.wikimedia.org/ci/job/mwext-mw-selenium-jessie/6581/artifact/log/Two%20column%20edit%20conflict%20help%3A%20RevisionSlider%20tutorial%20is%20not%20present%20after%20it%20was%20dismissed%20once.mp4
It also occurs on my local development environment shown below:
- Mediawiki Version: 1.31.0-alpha (1bb9a22) 03:01, 4 October 2017
- BetaFeatures Version: 0.1 (edfd490) 20:31, 30 September 2017
- TwoColConflict Version: 0.0.1 (a30c5f3) 09:23, 4 October 2017
The issue seems to only occur on fresh installations of mediawiki, therefore, it doesn't appear to be causing problems on the production server. Since, I use mediawiki-docker-dev for my local environment I periodically use new installations and thats when the issue was first spotted. This issue does not appear to be TwoColConflict specific and occurs with other BetaFeatures as well.