Linenumbers on by default

I just noticed line numbers are not displayed by default. I think this is a mad thing! Line numbers are the most useful thing, especially for a newbie, to see where an error is. Yes, the line highlighting also helps but especially when the compiler returns multiple errors line numbers are so useful. Also to be able to point to a line when helping on the forum. Any reason not to turn them on by default?

Start by locating the Arduino IDE 1.x editor preference that controls line-number visibility and inspect how its default is initialized. Confirm the behavior in a fresh IDE profile and check that the existing visibility setting still works; done when line numbers appear without user configuration.

Written by the indexing model from the issue text.