When you hold SHIFT (to sneak) + TAB (to open the tablist) + A (to move left) you would expect the player to sneak to the left while the tablist was open, but the player won't move at all. Long story short SHIFT + TAB + A doesn't move the player left while sneaking. The affected versions might be all the way to when the tablist was added.
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Duplicate of MC-54194
This may be an issue to do with key ghosting on your keyboard