- To prevent bustage and confusion of add-on compatibility, the major portion of Pale Moon version numbers will be in line with the toolkit/gecko revision that lies at the base of the browser. The current situation: although there are no intermediate major version numbers between the current version of Pale Moon (12.x) and the next major release, the version number will jump to match the version of the gecko engine/toolkit used as code base for the next major release of Pale Moon (15, in this case)
- Updates to the browser without a change of code base will result in minor version number increases (12.1, 12.2, 15.1, 15.2, etc.). Keep in mind that development and changes between these versions can be large and very significant, as they will involve patches from other "major" Firefox versions (backported or rewritten) and individually developed Pale Moon specific changes - overall compatibility in these "minor" (or not so minor) versions will, however, not be touched unlike in Firefox, so there won't be a danger of existing add-ons breaking with a minor version increase
- Remember that even though based on a certain version of the Mozilla/Firefox code base, Pale Moon can and will be significantly different in some respects than its sibling published by Mozilla. It will remain based on but otherwise unrelated to Mozilla Firefox. Don't expect Pale Moon 15.0 to exactly mirror Firefox 15.0 in terms of features and UI.
I've given this some thought and it is the best solution, also from a source-technical point of view.
Feel free to start a thread in the "General Discussion" board if anything in this announcement is unclear and needs to be explained further.