When you ride a strider on lava and save and exit the world whenever you join back you are burning, not a visual bug or glitch. You are actually burning and taking damage. Tested in Creative, Survival and Hardcore.
Environment
Windows 10 64-bit; Java 8; Java Platform SE binary 8.0.51.16;
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However, we are already tracking this issue, and this report is a Duplicate of MC-190266, which is a report that has not been resolved yet.
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