Lepton, formerly known as Proton Fix, is a Firefox theme project designed to enhance the overall feel of the new Proton design introduced in Firefox 89. The theme includes features like color contrast enhancements, dark mode support, compatibility with various systems, and customizable tab layouts. Installation can be done manually following a detailed guide or through an experimental script. The project addresses the improvements of Proton while acknowledging its flaws, offering a solution to users who prefer the previous Photon design. Lepton is supported by sponsors and contributors, with bug reports and inquiries being handled through specific channels.
https://github.com/black7375/Firefox-UI-Fix