Attribute is always showing as "Text Swatch" type in the admin panel

[wackget]

Magento CE 2.3.1

My size attribute is always showing as "Text Swatch" type in the admin panel even though it's a dropdown.

I have tried changing it to Dropdown and saving the attribute but then I run into this problem here:

https://github.com/magento/magento2/issues/22393

I have also truncated the swatch_options database table but this makes no difference - it's stuck as "text swatch" in the back end.

Backend:

Frontend:

[wackget]

P.S. I had to try submitting this forum topic FOUR TIMES before I was finally able to. First time I got an "expired token" message and lost all the post content(!) then I had "invalid HTML" error and lost all the post content again(!!).

Thankfully I'd copied the content to the clipboard, but the third attempt I got several errors about "this board requires a label" even though I'd entered two labels already...

Magento - including this forum - is seriously making me question my role as a web developer.