The jaxb implementation (com.sun.xml.bind 2.2.0) that was in Orbit for a long time had some dependency issues that have recently been uncovered by an attempted upgrade for 2020-06. Since 2020-06 release it has been possible to install two different features from simrel that create an incompatible set of classes (e.g. Linuxtools Docker + Mylyn Builds). This is made more complicated by the javax.xml.bind -> jakarta.xml.bind transition.
I have been working on resolving this issue, in the first instance I updated orbit's version of com.sun.xml.bind 2.2.0 to have the missing uses. This means that you can have the older (2.2.0) and newer (2.3.3) versions installed at the same time.
However it would be better* if we just had the 2.3.3 version everywhere, but that means rebuilding some projects. In particular there are projects that have require-bundle of javax.xml.bind that need to be updated to jakarta.xml.bind.
I am tracking this work in Bug 568379
and the dependent bugs. I am creating Gerrits for those projects that I know about, but they need to be committed and contributed back to simrel to complete this:
The successful resolution of this item would be to have no com.sun.xml.bind 2.2.0 and no javax.xml.bind in simrel at all.