Thank you for your comments. I think the comment that you updated Thomas is now more clear indeed. I have a comment about the default value of the property: unless I'm mistaken, "extension.localRepository" is the only property in xwiki.properties whose default commented value does not match the "actual" default ("actual" if the permanent directory is set to its default "/var/lib/xwiki/data/"), isn't it? What about aligning its default value with the ones used for the other properties which relate to a local folder, ie:

• store.file.directory: #store.file.directory=/var/lib/xwiki/data/store/file/ (current comment "The default is ${environment.permanentDirectory}/store/file")
• job.statusFolder: #job.statusFolder = /var/lib/xwiki/data/jobs/  (current comment "The default is {environment.permanentDirectory})/jobs/"

• solr.embedded.home: #solr.embedded.home=/var/local/xwiki/store/solr: this one should maybe be aligned to "/var/lib/xwiki/data/" as well?
• -> we could have as well #extension.localRepository=/var/lib/xwiki/data/extension/repository

As for the comment on the default value of these properties, we could use everywhere "The default is ${environment.permanentDirectory}[...]", what do you think?

(I'm turning this issue into an improvement rather than a bug)