>There is a nice solution in MacOSX where a folder opens if you hover >over it, however such a method may be patented. > Is it may be patented or already patented? Anyhow, Windows behaves like this also and that is the behaviour user can expect. So why not apply the patch like attached? It should implement spring on drag and written for 2.8, but it's easy to port it to recent sources.
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patch.diff
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