Reported in https://en.wikipedia.org/wiki/Wikipedia_talk:Growth_Team_features#Edit_suggestions_settings_not_completely_saved_immediately?

1. As a new user (or after clicking on "Restore all default settings" on Special:Preferences and re-enabling Homepage/Help panel again), go to Special:Homepage
2. On Suggested Edits (topic selection - step 1 out of 2) select some topics. Click Continue.
3. On Suggested Edits (task difficulty selection - step 2 out of 2) select Medium difficulty filters and click "Get suggestions". The correct set of suggestions will be loaded. The selected topics count will be displayed, e.g. 3 topics and "Easy, Medium" difficulty filters labels will be displayed too.
4. Click on the topic selection - despite on the correct counter display, a user will presented with the list of non-selected topics. The difficulty levels will be displayed as default selection (Easy tasks).

Note:

• The issue doesn't happen when selection is made after the initial selection - all selections are preserved
• the issue happens with the exact steps above: make an initial selection and immediately open the selection filters again