How do I reset to default window sizes in MacOS Safari's Responsive Design Mode? I use MacOS Safari's Responsive Design Mode for web development (Command-Option-R or 'Develop' &gt; 'Enter Responsive Design Mode' in the menu.
I have &quot;accidentally&quot; changed the largest window size to a random size (should be 1920 x 1080) by adjusting the horizontal and vertical handles. I would like to reset to 1920 x 1080, but it is very difficult to do by adjusting the handles because of the responsiveness of the controls; it's hard to stop on a specific dimension. Unfortunately, that is the only way I can see to do it, as I can't find a reset control or option anywhere?
I have searched the menu options and the almighty Google and can't seem to find an answer? I suspect there is .plist I can remove? Could someone point me in the right direction?
.This setting is written to Safari's preferences, that are located in ~/Library/Preferences/com.apple.Safari.plist in dictionary by ResponsiveDesignCustomPresetConfigurations key. So if you need to reset all responsive mode settings - just close Safari and delete that dictionary from prefs .plist file with following terminal command:

defaults delete ~/Library/Preferences/com.apple.Safari.plist ResponsiveDesignCustomPresetConfigurations