In 2016, a number of Mozilla employees and Debian maintainers argued that the branding was no longer needed, and on 10 March 2016, Debian's unstable branch switched back to the Mozilla branding, with the stable branch planning to switch after Iceweasel's end of life. In July 2007, Iceowl, a rebranded version of Mozilla Sunbird, was added to the unstable branch of Debian. These changes were implemented in the subsequent version of Debian (Etch). The new names established by Debian were Iceweasel for Mozilla Firefox, Icedove for Mozilla Thunderbird, and Iceape for SeaMonkey. The Debian Project subsequently rebranded the Mozilla Firefox program, and other software released by Mozilla, so that Debian could distribute modified software without being bound by the trademark requirements that the Mozilla Foundation had invoked. At issue were modifications not approved by the Mozilla Foundation, when the name for the software remained the same.

In 2006, a branding issue developed when Mike Connor, representing the Mozilla Corporation, requested that the Debian Project comply with Mozilla standards for use of the Thunderbird trademark when redistributing the Thunderbird software.

Mozilla thunderbird license