How to get to the correct documentation page?

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Suppose I'm trying to look up the documentation for geometry_msgs.

1. I start from https://docs.ros.org/melodic/api/ (which I perceive to be the root of the ros documentation)
2. Find the geometry_msgs folder (https://docs.ros.org/melodic/api/geometry_msgs/)
3. Open the html folder (https://docs.ros.org/melodic/api/geometry_msgs/html/)

However, that is just a dummy page. The correct page I'm expecting is actually http://docs.ros.org/melodic/api/geometry_msgs/html/index-msg.html

I couldn't quite figure out a way to get to that page from the documentation root and the only way of getting to the correct page is by googling. It seems rather unintuitive that the correct documentation pages can only be found by google and not by navigating through the documentation itself. This also makes finding less commonly linked documentation (which may not appear in google searches) more difficult.