Annoying dashed line in the center of my canvas

HI everyone, I was using mypaint quite successfully until I did something, clicked something attempting to undo a brushstroke that has made a white, vertical, dashed line appear in the not quite center of my “artwork”. It is making me so angry and I can’t make it go away. Can you pretty please help?

Thanks!!
ret

HA. this was me, somehow, activating the symmetrical painting option. annoying line gone. thank you so much!!

“U” is the shortcut key for that. Ctrl-U will let you move it around and if you use the Window Item at the top and chhoose the tool options panel, you can create more lines of symmetry as well as change the type that is applied. It is VERY useful for drawing faces and objects. Saves a lot of work as you only have to draw half of the face… It also makes filling things in a lot easier (unless you are filling with the bucket … buckets are ignored on almost every program when using symmetry /shrug)

~Tigr~~,