So, yesterday I was uploading some new texts, when I realized the button was gone and it was an editable text witch said upload.

I pressed enter and everything turned out fine.

But still, where is tha button and why is there a editable text?

It was like that for awhile. Click on it so u can type and click enter and it should upload.

Is there any explanation of WHY this is happening?

if you use the textures tab in the shop it still works fine

otherwise just click in the box and hit enter

But shouldn't it be fixed?