plains how to turn off the hex-line-number f

Yes, the issue is from CustomLineNumbers. I change to not active mode, and the line number is back to the decimal mode.

Thanks

The usual culprit is the plugin CustomLineNumbers. This post explains how to turn off the hex-line-number feature. Or, if you are neither using hex line numbers nor changing the first line number, uninstall it (as Alan suggested) since then it’s a completely useless plugin to you.

Remove the plugin that is doing this. I don’t remember the name exactly but if you look at your plugin list it should be obvious.