This glitch is simple enough: items modified to have the §k tag tend to be unstable in rendering text. I don't mean in the way it's intended: the entire string, even that which is not supposed to be affected by the §k tag, will distort and break at random intervals (usually around a second at most) for a split moment. This extends to the chat, including the kill message if you kill a player. Given the tiny window where it is displayed, I can't provide a screenshot.
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Comments 4
Violine, it does explain half of my issue; however, not the other half. The issue is most noticeable when you kill another player or a tamed wolf with an item containing the §k string and view the message that appears in chat; occasionally, the whole message just won't display right. I wish I could get a screenshot of this, but the effects are displayed for such a brief moment that I'd have to record a small video for it to display the issue.
How about MC-134865?
Does MC-134879 describe your issue?