Adding reload/restart dialog

[echomehran]

Adding reload/restart dialog

Summary

Hi, I like your project and I've been using it recently. but I found a missing dialog in the Preferences part because when I hit Enable fixed-width layout I have to reload the page or if I have it installed on my chrome browser I have to restart the app to take effect, so I thought it would be good to add a dialog in front of the text as I did in the picture below, and also if it's possible I would like to contribute and send a pull request if I'm allowed.

Thank you :)

Examples

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