VARBINARY and BINARY columns display incorrectly in some situations after editing them.

I use BINARY(16) and VARBINARY(16) columns to store UUIDs in my database. HeidiSQL is the only porgram so far that can properly deal with these. But recently (possibly since upgrading to 9.4) I've started encountering this weird bug, sometimes.

If I edit one of these columns in HEX or Text mode the popup displays less text or hex-characters then the expected 32/16 characters. It appears some of the characters go missing. If I cancel the edit operation the characters show up incorrectly in the overview as well, but it's not registered as a change (I can move around without triggering any updates). If I press F5 everything turns back to normal.

The length of the remaining UUID seems to be variable and I haven't found a pattern. It kinda seems like some of the bytes get interpreted as UTF-8 and get truncated after they get converted back to binary or something?