If I'm eating an item and have blocks in my off-hand, holding right click will eat until my hunger bar is full then immediately place a block. This is kinda annoying and I would maybe expect to need to release then re-press right click to use the off-hand.
I've also done this with an axe in the off-hand, accidentally stripping a log. Also with a spyglass in the off-hand, abruptly zooming in when done eating (which is visually annoying but not too bad).
I think with some things this behavior could be convenient sense, like with a hoe in the main-hand and seeds in the off-hand, you can hold right click to continuously till the land then place seeds. But with eating (and maybe other things?) I think it's a little troublesome.
Thank you for your report!
We're tracking this issue in MC-135143, so this ticket is being resolved and linked as a duplicate.
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