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This has been the case ever since Jagex flattened the 'Invert Paths' and 'Unlock' buttons and changed their looks a couple of months ago. Now it often gives a 'Failed to find puzzle elements' message when clicking the usual 'Unlock Any' button and hovering to invert paths never works now. The only way to make it work sometimes is by turning the puzzle until two or more runes overlap and give green to give the solver more to detect. This wasn't always the case and it's almost certainly because originally the interface looked like this:
And now it looks like this for me:
Here's an example of Alt1 not detecting the puzzle when there are zero overlaps:
And here is Alt1 giving the solution after making two runes overlap:
I know that I might be the only person that still uses the legacy interface so I apologize for the inconvenience.
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