Change default keyword for Firefox search engine

[kema-dev]

Extension's manifest adds Leta as search engine, and sets the default keyword to m as per this line.

browser-extension/src/manifest.ts

Line 59 in ab7e708

keyword: 'm',

However, I would like to use this keyword for another search engine.

Currently, the m shortcut is hard coded in the manifest and forced each time I restart my browser, thus I can't use it for another search engine.

Do you think that setting it to @mullvad, @leta or whatever would be ok ? This would comply with Firefox's default search engines.

[ruihildt]

Changed it to leta.

This will be part of the next minor release.