I searched this error and based on what is in this forum re-installed Lastpass app from a post here (https://www.microsoft.com/en-us/store/p ... zdncrfj3qk
1. Installing the app works, but no extension shows.
2. From Win Store clicking Launch opens the app and I can login correctly. BUT still extension does not show.
3. TRying to sideload the extension from the WindowsApps folder under /Program Files/WindowsApps/Lastpass.LastPassFreePasswordManager.4.1....../Extension gives the following error
"Manifest parsing error: Invalid value for "key" field"
Can this please be fixed.
4. Even after complete reset - COMPLETE -of Edge browser the app installs but extension does not load.
5. Sideloading is done after enabling 'developer' mode in Edge using about:flags.
Fix needed !