Hello, I understand that you are experiencing an issue where tabs automatically close when you open a bookmark or perform a search in the address bar in Firefox on Linux Mint 21.1 Vera, using Firefox version 115.0.2 (64-bit). To address this issue, there are a few troubleshooting steps you can try: Clear cache and cookies: Sometimes, corrupted cache or cookies can cause unexpected behavior. Go to Firefox's Preferences/Options, select "Privacy & Security," and under the "Cookies and Site Data" section, click on "Clear Data" to clear cache and cookies. Disable extensions: Some extensions can interfere with tab behavior. Try disabling any installed extensions one by one and check if the issue persists. Refresh Firefox: Firefox has a built-in feature called "Refresh Firefox" that can fix many issues. To do this, go to the Firefox Help menu, select "Troubleshooting Information," and click on the "Refresh Firefox" button. If the issue continues after trying these steps, it would be helpful to gather more information to diagnose the problem. Can you provide any specific error messages, or do you notice any patterns when the tabs close? Please let me know the results of the troubleshooting steps or any additional information you can provide, and I'll be happy to assist you further. Best regards, Suram Firefox Support Volunteer