rsx11m wrote:Current plans for Thunderbird include to follow the 17.0 ESR (extended support) branch with releases until a new ESR branch is opened (see the summary and detailed posts on tb-planning) ...
- SM follows what TB did and produces releases after 2.14 against mozilla-esr17, which would ensure stability for the duration of this branch but may delay new features from entering the releases (thus, in essence the pre-rapid-release status);
- SM stays in the rapid-release scheme and builds against current mozilla-release, thus picking up improvements in the browser, but possibly introducing instabilities in the mail/news part given that there is less incentive from the Thunderbird side to fix regressions introduced by Core changes.
As an update, option #2 is what we will see with the upcoming SM 2.15 release next week. If you look at comm-release you will notice that its release branch comes off the default branch after merging from comm-beta, whereas the TB 17.0.2 release branch was cut off the default branch before merging and thus mirrors the 17.0 ESR state (the same happened on mozilla-release).
This is an interim solution on the Thunderbird side given that actually building TB 17.0.x off comm-esr17 has been delayed (bug 815302). This is expected to be implemented with the next (Gecko 19.0) cycle.