Description
VoiceOver will sometimes treat a press of up or down arrow like moving by character, even though Quick Nav is off. I cannot reliably reproduce it, but it has been a problem since 10.8 or earlier. I have only ever seen it happen while editing text. Note that this is very rare, but it does happen.
Comments
key mash-ups
I believe this behavior is related to a wider problem where the Mac thinks another key is being pressed. On both my MBA and MBP, quiknav sometimes is turned on simply by my pressing the right arrow key by itself. Similarly, sometimes one computer or the other will think the command key is being depressed, as evidenced by what happens or doesn't happen when I press other keys. When turning VO off on my late 2016 MBP to reboot it (which, unfortunately, I have to do frequently because of bugs), it often thinks I'm holding down the spacebar and tries to evoke SIRI, even though I've only pressed the command key. Etc. Keys would also get ghost-pressed in Boot Camp on my MBA--either alt or Win. Years back, I had at least one Dell Lattitude with the same sort of issue. In all cases, finding out which key it thinks was pressed and rapid-pressing it a time or two unsticks it, which corresponds to why turning quicknav on and then off would work (again, sometimes I've actually found quicknav on, even though I'm quite certain I was just hitting the right arrow key through a document and was nowhere near the left). I think it is happening in the membrane or butterfly mechanism beneath the keyboard. I suspect it's not particulate matter, which I've also experienced, but rather strain on the chassis from either my palm or how the machine is resting. Whatever the case, phantom keystrokes among the command and cursor keys are a problem.