I would assume that warped and crimson planks and stems don't burn because they are from the nether, however you can still use the planks in a furnace and they have the same cook time as regular planks like oak. Unlike the planks, Warped and crimson stems cannot be put into the fuel slot of a furnace.
MC-171087
Warped and crimson planks/stems do not burn
Resolved
Duplicate
0
Maxwell Wright Heck
(Unassigned)
Unconfirmed
(Unassigned)
20w06a
Retrieved
Thank you for your report!
We're actually already tracking this issue in MC-171005, so I resolved and linked this ticket as a duplicate.
However, that ticket has already been resolved. That means that this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
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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