I've always noticed that the left side is a little flaky, in terms of characters not getting displayed when they should, particularly when pressing up/down to go through recent commands. Like you report, a few more characters always seems to sort it out.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
I've always noticed that the left side is a little flaky, in terms of characters not getting displayed when they should, particularly when pressing up/down to go through recent commands. Like you report, a few more characters always seems to sort it out.