When drawing lines, don't style the active drawing vertex as a large endpoint

[bhousel]

@bhousel

It occurred to me to investigate further. With the area tool the disc under the crosshair is small, like I remember the disc under the line tool used to be. Which is why I hadn't noticed any difficulties using the area tool. It also gave me a useful comparison to confirm my feeling that it's much harder to use the line tool with the larger disc under the crosshair.

Originally posted by @eehpcm in #5701 (comment)