Add `temporarily_allow_weak_signatures` to `ExtensionSettings`
| `restricted_domains` | An array of domains on which content scripts can't be run. This setting can be used only for the default configuration.
| `updates_disabled` | (Firefox 89, Firefox ESR 78.11) Boolean that indicates whether or not to disable automatic updates for an individual extension.
| `default_area` | (Firefox 113) String that indicates where to place the extension icon by default. Possible values are `navbar` and `menupanel`.
+| `temporarily_allow_weak_signatures`| (Firefox 127) A boolean that indicates whether to allow installing extensions signed using deprecated signature algorithms.
**Compatibility:** Firefox 69, Firefox ESR 68.1 (As of Firefox 85, Firefox ESR 78.7, installing a theme makes it the default.)\
**CCK2 Equivalent:** N/A\