Steps to repro:

1. Find a decl that contains a link to a decl m.d in another module m.
2. Collapse m in the module tree and refresh to make sure that collapsed state is persisted correctly to localStorage.
3. Click the link you found to m.d.
4. Observe that while m will be highlighted in the module tree, and the page will correctly show the decl panel for m.d, m will still be collapsed in the module tree.