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Firefox 79.0 Closes Immediately on opening

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  • Last reply by fberlack

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Once Firefox 79.0 is installed on my two Windows 10 systems, it opens for a second and closes immediately. If I open Firefox from a link in my email, it opens without crashing. If I select open a new window it opens and closes immediately. If I select Open a New Private Window, it works. If I open a new tab it works. If I select Open a Link in a New Window, it works. The same problem happens why attempting to open Firefox in Safe mode.

Once Firefox 79.0 is installed on my two Windows 10 systems, it opens for a second and closes immediately. If I open Firefox from a link in my email, it opens without crashing. If I select open a new window it opens and closes immediately. If I select Open a New Private Window, it works. If I open a new tab it works. If I select Open a Link in a New Window, it works. The same problem happens why attempting to open Firefox in Safe mode.

Modified by fberlack

Chosen solution

Open the browser using a link. After, check the Home Page setting.

https://support.mozilla.org/en-US/kb/how-to-set-the-home-page

Type about:config<enter> in the address bar. If a warning screen comes up, press the I Accept the Risk button. At the top of the screen is a search bar. Type browser.startup.homepage

What is the value? Right-click and select Reset to restore its default value; about:home

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Chosen Solution

Open the browser using a link. After, check the Home Page setting.

https://support.mozilla.org/en-US/kb/how-to-set-the-home-page

Type about:config<enter> in the address bar. If a warning screen comes up, press the I Accept the Risk button. At the top of the screen is a search bar. Type browser.startup.homepage

What is the value? Right-click and select Reset to restore its default value; about:home

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Thank you for the advice. The startup home page was set to "browser.startup.homepage https://my.yahoo.com/closeloginpopup.php." I reset it and changed it back to https://my.yahoo.com and it appears to be working correctly.