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localhost URL automatically becomes www.localhost.com invalid URL "smart yet dumb"

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  • 2 have this problem
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  • Last reply by cor-el

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I have MAMP installed on my Mac. I have used Firefox with it happily for years. With latest update, my required URL gets converted from http://localhost:8888/MAMP/?language=English to invalid URL http://www.localhost.com:8888/MAMP/?language=English (http:// not displayed of course). If I edit it in the address bar, it still gets converted to the invalid 'correction' and I can't reach the website on my own machine! I see there is a way to remove unwanted suggestions and presumably I can do this to prevent the substitution - but it shouldn't be necessary! Andy Macdonald

I have MAMP installed on my Mac. I have used Firefox with it happily for years. With latest update, my required URL gets converted from http://localhost:8888/MAMP/?language=English to invalid URL http://www.localhost.com:8888/MAMP/?language=English (http:// not displayed of course). If I edit it in the address bar, it still gets converted to the invalid 'correction' and I can't reach the website on my own machine! I see there is a way to remove unwanted suggestions and presumably I can do this to prevent the substitution - but it shouldn't be necessary! Andy Macdonald

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Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences in the address bar and press Enter.

Select Advanced > General. Look for and turn off Use Hardware Acceleration. Then check ALL of your settings; Browser and add-ons.

Poke around safe web sites. Are there any problems?. Then restart.

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Does "Forget About This Site" in the right-click context menu for such a www.localhost.com help?

Such issues can be caused by using a proxy to connect. You can also try to disable the fixup.

  • browser.fixup.alternate.enabled = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.