The tree of components in a project is compressed by collapsing folders containing a single folder into the parent folder.
For example, a java project that has no tests sources and no resources will have a single item src/main/java.
However, this is not working correctly for pull requests and short lived branches. The algorithm to compress paths is applied over the entire tree of components (whether they are changed or not), but then we only actually save folders containing changed or new files.
As a result, some folders aren't collapsed even though they could be, because of files that were pruned from the tree for being unchanged.