Kindle reader developed a fault that does not appear on Opera browser
For over a year, I've used my Firefox browser to read the Kindle books. In the top right corner there should be six icons representing 1. Table of contents 2. Search 3. Reader settings (size of font and one or two columns) 4. Annotations 5. Add bookmark 6. Reader menu - this should have five dropdown items including "go to page" which is missing. It now only displays the first and the last, and I want to use "go to page" which is missing.
Another failure of going to the right page - when I log into Firefox on my desktop after browsing Kindle on my Kindle reader, Firefox is meant to go automatically to where I have been reading on the table. Instead it goes to the beginning of the book. That looks like the same problem - failure to go to the right page.
It works fine on Opera but I have to look up my passwords and type in the URL, whereas my Firefox browser shows Kindle along the top, and my password manager works for Firefox. So Opera is very inconvenient.
I guessed that my version of Firefox has become corrupted, but couldn't find how to re-install it.