Indesign page thumbnails showing blank

Man, I am so sick and tired of having all these new glitches / bugs appearing with every single release of InDesign... we don't need these headaches Adobe – can't you get anything right? What's going on with your developers, they lack simple attention-to-detail and keep breaking stuff! Been going on for years now, and am completely over it!

I had the same issue for weeks, it's very disturbing, it's making my work a lot harder to not have thumbnails in the pages. Today I solved the issue. I had the blue circle circling at the right top of my Indisign, signing that something is downloading, but nothing happened. If you click on it, you can see the background tasks, and it showed that the InDesign is trying to download an Adobe font. The strange thing that it's a variable font, and it couldn't download other weights of the same font, although I could actually use them in my file. The only solution was to delete all the text with the 'missing' font (or change the font to another one) close the InDesign (and probably all the Adobe programs), and reopen the file, and since there was no 'missing' font, all the thumbnails were loaded again. You have to close the InDesign for it to work, because even if you delete all the text from your document, and nothing is wrong with the other open InDesign files, it's still trying to dowload the 'missing' font, and it somehow stops all thumbnails to appear in the Pages view.

Open the pages panel menu and click on panel options. Do you have thumbnails enabled?