Flattycakes

A Gimp 2.10 icon pack.

Click the green "Clone or download" > "Download ZIP" option at the top of this page.
Unzip the file to see its contents
Move the flattycakes-icon-theme folder to the location specified in the GIMP settings: Edit > Preferences > Folders > Icon Themes (On Ubuntu it's likely ~/.config/GIMP/2.10/icons or /usr/share/gimp/2.0/icons/)
If GIMP is currently running, close out and restart
Go back to the settings (Edit > Preferences > Interface > Icon Theme), select "flattycakes" and press "ok" to apply. You should see the updated icons instantly.

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