
You can disable Push notifications in Firefox by changing ‘dom.webnotifications.enabled’ preference value to ‘false’ in about:config, but this no longer working in Firefox 57 Quantum.
To address that and to allow users to block notification prompts shown by websites easily, Mozilla now offers a new option in Firefox 59 Permission settings for Location, Camera, Microphone and Notifications in Preferences.
FYI, Web Push Notifications feature has been abused by Websites, makes it impossible for users to turn off globally in Firefox.
READ: Firefox 44: Mozilla adds Do Not Disturb button for Notifications in Nightly
Block Web Notifications in Firefox from Preferences
1. Click on Menu, select Options
2. Click on Privacy & Security > Permissions > Notifications,
3. Click on Settings
4. Check ‘Block new requests asking to allow notifications’ and click ‘Save Changes’

Disable or Block location requests in Firefox
If some websites such as Google are requesting for access to your location in Firefox browser
1. Visit Menu > Options > Privacy & Security > Locations,
2. Click on Settings, check ‘ Block new requests asking to access your location’, click Save Changes’.

Similarly, you can also able to block requests from Websites that ask you to allow access to your Camera or your microphone by accessing their settings and checking the option at at the bottom.
You should also know these changes happened recently in Firefox 59, Mozilla has removed Firefox health Report and the add-ons Manager search in the new version to use AMO Search.
Firefox 59 : Mozilla removes Firefox Health Report
Firefox 59: Add-ons Manager Search to Use AMO Search [Via Soeren]