Crimson and Warped wood variants will catch fire from lava incorrectly. I have explicitly observed this with the stems and planks, but suspect all items equivalent to wood items that would catch fire from lava will experience the same issue. (e.g. hyphae, stripped stems, stripped hyphae, etc.)
Thank you for your report!
We're actually already tracking this issue at MCPE-69149, so I will resolve and link this ticket as a duplicate.
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