The Qt Company Is Tomorrow Moving Qt 5.15 To Its Commercial-Only LTS Phase

Written by Michael Larabel in Qt on 4 January 2021 at 11:26 AM EST. 93 Comments
As part of their fundamental shift to restrict Qt LTS point releases to commercial customers, The Qt Company is closing the Qt 5.15 branch to the public tomorrow with future Qt 5.15 LTS point releases to be restricted to paying licensees.

The notice was sent out today that beginning tomorrow (5 January) will start the commercial-only LTS phase of Qt 5.15. The existing Qt 5.15 branches will be publicly visible but will not see any new patches. The public branches are closed to new commits with the exception of Qt WebEngine and the deprecated Qt Script due to third-party LGPL dependencies.

Only active, commercial license holders will be able to access the private repository that will have the code that comprises the future Qt 5.15 LTS point releases. The first commercial-only Qt 5.15 LTS tagged release is expected to happen in February.

Qt 5.15 LTS going commercial-only while Qt 6.0 is in a very primitive state still has irked some users and developers already. The fact that the Qt 5.15 branch is being locked down midstream is also irritating some who have worked on fixes for regressions from earlier Qt 5.15.x point releases only now not to have a public release with those regression fixes.

Those outside of The Qt Company that contribute to the Qt toolkit are also ticked off over this move. Longtime Qt contributor Thiago Macieira of Intel was quick to comment that at lest for code he deals with in Qt, he will not be participating in fixes or commenting and reviewing on back-ports or bug reports. He intends to just close bug reports that cannot be reproduced on Qt 6.0.

The less than stellar state of Qt 6.0 was also brought up in the thread given that only "half of the modules" from Qt 5 are available in Qt 6 so far, Qt 6.1 might end up having ABI breakage (to be determined), and the overall state of Qt 6.0 not being too ready for end-users yet. The first Qt 6 LTS release won't be until Qt 6.2 in just under one year's time, leaving a large gap for those open-source users/vendors/distributions that tend to just ship/use Qt LTS release series. Like Qt 5.15, Qt 6.2 is confirmed to be another commercial-only LTS under the same process.

There is a bug report calling for "-free" branches of Qt 5.15 to be maintained by those interested in the community. But no developers from The Qt Company have yet responded to that proposal, which they may very well dismiss considering it could detract from potential paying customers. Otherwise the current state of the Qt 5.15 branch could be forked elsewhere and maintained by those interested in a community Qt LTS version. Inevitably this is probably what will occur given the mass amount of Qt5-based open-source software out there and with Qt6 porting taking time plus a number of modules currently missing, the transition to Qt6 will be very gradual even with no more official Qt 5 public releases planned.
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