So something of a bug I encountered when setting up a course, is that if a database field contains ‘regular’ spaces, then full width spaces will always be converted to this space style despite being typed in again.
I found this when creating an entry for the following:
わたし は 〜 です
I copied this from a document, and then realised it had taken regular spaces. When I went back to change it to full spaces:
わたし は 〜 です
The changes appeared on the page, but upon saving, refreshing, or going to another page these reverted to normal spaces. I tried deleting the field and re-entering, but to no avail. I also tried adding the same sentence after the half spaces, so I could delete the first half later:
わたし は 〜 ですわたし は 〜 です
But this reverts as well. The only solution I found was to create a new field and re-enter the data.
With some further testing, I found that if an entry has full spaces, these will be converted as soon as a regular space is entered. In other words, as soon as a regular space enters the field somewhere, it can’t contain full spaces again.
This seems like a strange bug, and it’s not too bad to work around, but it can be annoying to re-enter data when you want the full spaces.