Nie pomaga instalacja Firefoxa od początku :(

Can You speak english? Sorry I don't Understand.

Does the Firefox Password Manager work properly ?

Firefox uses the Password Manager to store the credentials of the Firefox Sync account (chrome://FirefoxAccounts) to make it possible to connect to Sync each time you start Firefox without the need to enter email and password. If you use the master password then you need to enter this MP every time you start Firefox. If you are asked to login again to Sync then this means that the Sync credential data isn't stored properly in the Password Manager. Once you are logged in to Sync then the signedInUser.json file in the profile folder is used to connect to Sync during the current session. You can check if you have a logins.json.corrupt file in the profile folder.

You can use the button on the "Help -> More Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

• Help -> More Troubleshooting Information -> Profile Folder/Directory:
  Windows: Open Folder; Linux: Open Directory; Mac: Show in Finder
• https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data