The Minecraft devlog for 20w13a states that striders can stand and walk on other mobs. While this feature is prominent, I found out that if you ride a strider on top of mobs for a while and then use warped fungus on a stick to move, it sinks into the mobs below and even takes damage while doing so.
Thank you for your report!
We're actually already tracking this issue in MC-176015, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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