Previous versions of Firefox switched the Home Screen shortcut boxes (sites you save or visit) from showing a mix of site icons and screen capture thumbnails to just icons. The method to switch back from icons to thumbnails was to go to “about:configure”; type “newNew”; Double-click the browser.newtabpage.activity-stream.newNewtabExperience.enabled preference to switch the value from true to false.
That worked for me in versions 89 ~ 93. But that does not work for version 94. Does anyone know how to switch back from bland, generic icons to specific thumbnails?