Maybe you've made a right mess of things and want to start over? Or maybe you're using the auto router plugin and want to make sure random junk isn't going to ruin things.
You could run the menu command to delete all non-locked tracks then refill the zones. Or you could push this 1 button which is just easier and faster.
This plugin will nuke all tracks that are not locked on the board* then automatically regenerates any zones.
Have regrets? A single undo will put it back to how it was before the plugin ran.
* By not deleting locked tracks you can choose to keep anything you're happy with and have locked.
- Click the green "Code" button in the top right and select Download ZIP.
- Extract that zip file to somewhere you will remember.
- In the PCB design window select the menu item Tools > External Plugins > Reveal Plugin Folder in Finder/Explorer.
- Copy the extracted files into the plugin folder that you just opened.
- Close and re-open the PCB deign window.
You should see the nuke icon in the top menu bar.
or if you're the type to understand this
cd [path to you kicad scripting folder]/plugins
git clone https://github.com/themaninthesuitcase/kicad_nuke_tracks_plugin.git
Icon by Lorc under CC BY 3.0 https://game-icons.net/1x1/lorc/mushroom-cloud.html