The term "history" has two possible meanings: one is just narrowly the pages you have visited and when you visited them, and another is all your personal data. For example, if you use the Clear Recent History dialog and expand it to show the checkboxes, you can see what might be cleared in that process. But I'm getting ahead of myself. Could you try these two diagnostic tests to see whether we can narrow down the cause of the problem? (1) Firefox's Safe Mode This is a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: [[Troubleshoot Firefox issues using Safe Mode]]. You can restart Firefox in Safe Mode using either: * "3-bar" menu button > "?" button > Restart with Add-ons Disabled * Help menu > Restart with Add-ons Disabled Not all add-ons are disabled: Flash and other plugins still run After Firefox shuts down, a small dialog should appear. Click "Start in Safe Mode" (''not'' Reset). Any difference? (2) Disable Flash until you approve it By default, any site can use Flash. This permission setting changes that so sites can't use Flash without your approval. This can help diagnose whether the Flash plugin is responsible for the non-responsiveness. Open the Add-ons page using either: * Ctrl+Shift+a * "3-bar" menu button (or Tools menu) > Add-ons In the left column, click Plugins. On the right side, look for "Shockwave Flash" and change "Always Activate" to "Ask to Activate". Now, when you visit a site that wants to use the Flash, you should see a notification icon in the address bar and one of the following: a link in a black rectangle in the page or an infobar sliding down between the toolbar area and the page. You only need to allow Flash if it looks as though it would be helpful. Any difference?

hello, The following article would help you: [https://support.mozilla.org/en-US/kb/delete-browsing-search-download-history-firefox The article.] Thank you.