Make me a Sticky? Clear cache on package update if things go weird

Well, after a long session with @robertl one thing is clear: if the PL package has recently been updated, the browser cache should be cleared.

Cache clearing on version change might be coded into the package, but if in doubt, Ctrl+Shift+Delete for e.g. Chrome to clear files is a good 1st step before spending too much time logging issues or investigating.