I did "flip horizontally" to my Photoshop image, and all the text in it got flipped horizontally as well. I'm talking about unrasterized text-- still in a "Text Type" layer. Now even if I edit the text and add letters, they all come out mirrored. How can I cancel this behavior? I want to make the text normal again.
I haven't got Photoshop installed on this computer to double check the exact sequence of commands, but if you deselect the text layer you should just be able to flip the image on its own.
Alternatively if you've already got some mirrored text, just select that layer and flip that back.
The only other thing I can suggest is to lock the "text" layer when you start mirroring and unlock it afterwards.
Flipping an image ("canvas") and the actual layer is two different things. You obviously want to flip the "layer" the image is on, not the whole "canvas".
It's under the "Edit" on the menu. "Edit / Transform / Flip Vertical".