tumblr controls missing
Hello, ever since about 3 days ago, the controls on tumblr have gone missing in my browser. At first, I had it happen in every browser and in the private mode, but after a day of that, it is now only happening in firefox anymore.
Explanation, in case it's unclear what I'm talking about: On every blog on tumblr that you open (URL.tumblr.com, for example https://staff.tumblr.com is the link to the blog of the tumblr-staff if you'd prefer an actual blog to look at), in the top right corner of the page, there should be a few buttons, depending on if it's your blog or if you're logged in or not varying between 'follow' and 'join tumblr', 'edit post', 'edit appearance', 'reblog' or 'like', things like that.
- I'm not sure if that part helps with solving the issue, so just in case: From what I can tell, the controls use codes of iframe to work.
- It is not specific to one blog on tumblr, the controls are gone on every blog/page I open.
- I opened the pages in private mode and the controls are there. When I go to add-ons and disable everything, the controls still are not showing up though, so I don't think any add-on can be the cause.
- It did work until a few days ago, and I didn't change any settings in my browser during the time.
- I'm using the newest version of firefox (77.0.1), or at least I'm not getting shown any updates left to do in the 'about firefox'.
All that I can still think of to do is to try to refresh, or if that doesn't work completely un- and reinstall firefox, or maybe try an older version of ff if that still doesn't help, and I would really rather find a solution without taking such big measures, which is why I am asking here.
Is there maybe something else that private mode does that I could try to do to fix this?
Thank you in advance for the answers I might get!