It’s not something I recommend to use for XAR extensions generally as the meaning of this option is not to execute “Install” on each existing wiki, it’s a special install which force this extension and all its dependencies (which is the problem here) to be available on all present and future wikis.
What happen is that since you told XWiki to install “Numbered Headings Application” on farm, it did: this implies to also install all its dependencies on farm too (unless they are already available) and one of those is a very different colliding version of ckeditor (org.xwiki.contrib:application-ckeditor-ui instead of org.xwiki.platform:platform-application-ckeditor-ui). It’s not a problem when org.xwiki.platform:platform-application-ckeditor-ui is already available where you need org.xwiki.contrib:application-ckeditor-ui because it indicates that it “includes” it as a feature, but here there was nothing on farm, so it installed the dependency recommended by the extension.
The main bug here is that it should not have allowed you to do it as the install plan is supposed to check that all modifications made are not going to break existing extensions in terms of required dependencies, but it seems that here it did not take into account the flavors backward dependencies for some reason, so I will try to debug that.
Ideally, what you should do is revert your changes and put back the expected extensions:
- from main wiki, uninstall
CKEditor Integration 1.60.1: this should uninstall the wrong ckeditor andNumbered Headings Application 1.7.1 - from main wiki
RepairXWiki Standard flavor: this should install back the missingCKEditor Integration 14.6on the main wiki - from other wikis,
RepairXWiki Standard Flavor for sub-wikis: this should install back the missingCKEditor Integration 14.6on the main wiki