You can set Firefox to ask you each time. That would be on the Preferences page.

• Mac: "3-bar" menu button (or Firefox menu) > Preferences
• Linux: "3-bar" menu button (or Edit menu) > Preferences
• Windows: "3-bar" menu button (or Tools menu) > Options
• Any system: type or paste about:preferences into the address bar and press Enter/Return to load it

If you scroll down to the "Files and Applications" section, you'll see a pair of radio buttons to change from a preselected folder to asking you each time.

Does it work for you?

No. It still only offers me to save in the download folder or open?

If you choose "Always ask you where to save files" then when you select Save File and click OK, Firefox should show a dialog that lets you choose any location on your system. Not working that way?

You can try to set this pref to false on the about:config page.

• browser.download.useDownloadDir = false

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

• Help -> Troubleshooting Information -> Profile Directory:
  Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
• http://kb.mozillazine.org/Profile_folder_-_Firefox

Thank you! Problem solved. Have a good day