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I want Firefox to open in a maximized window

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  • Last reply by cor-el

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That used to happen for years. About 2 months ago Firefox began opening with a 'restored' (i.e. not maximised) window. For a few days in the last fortnight it resumed opening maximised. Now it is opening with a 'restored' window which is wider and shorter than the size used previously.

The localstore.rdf file is dated 09 May 2014.

That used to happen for years. About 2 months ago Firefox began opening with a 'restored' (i.e. not maximised) window. For a few days in the last fortnight it resumed opening maximised. Now it is opening with a 'restored' window which is wider and shorter than the size used previously. The localstore.rdf file is dated 09 May 2014.

Chosen solution

Note that current Firefox releases haven't used localstore.rdf for quite some time and that only xulstore.json is used to store data about windows.

The window size is no longer stored (sizemode: normal;) and thus is it impossible in current releases to force a maximized window or full screen mode on startup.

See also:

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You may have a corrupt xulstore.json or Localstore.rdf file.

https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved

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Thank you. I will try deleting xulstore.json. That file is dated today so I am guessing it is created daily. I am reluctant to delete localstore.rdf because I will then have to re-customise the browser from scratch.

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With Firefox closed you could try editing the localstore.rdf file.

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Thanks. What amendments do you suggest? Is there an entry relating to the opening window state?

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It may be worth noting that if you rename localstore.rdf whilst firefox is closed it will be recreated when it restarts. If the problem goes away you know that localstore.rdf was part of the problem.

Comparing the two versions of the files may help to identify the problem. Make additional versions and try editing and renaming them to fix the issue.

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Chosen Solution

Note that current Firefox releases haven't used localstore.rdf for quite some time and that only xulstore.json is used to store data about windows.

The window size is no longer stored (sizemode: normal;) and thus is it impossible in current releases to force a maximized window or full screen mode on startup.

See also:

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Similar issue

Firefox overwrites window manager rules by restoring window size / position after startup

>OS GNU/Linux >Firefox 52 >WM Openbox

>What happens /0 Start Firefox /1 Firefox window is maximized as per Openbox rule /2 Firefox window is resized to before closed previous state

I know this because it does not maximize if I turn off the Openbox rule it starts with /2 instead

I would like to disable /2 i.e. remember size / position before close

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Hi bygabyga

I don't think that that is possible. Firefox no longer stores the maximized and full-screen mode state in xulstore.json, but stores the last unmaximized settings like I posted above. So Firefox will always with the last used settings or with the defaults if you would clear this data from xulstore.json. You can check this for yourself by inspecting the xulstore.json file and modifying the main-window section.

"main-window":{"screenX":"44","screenY":"-12","width":"1280","height":"920","sizemode":"normal"}