
I use TeXnic Center, and somehow I managed to push some combination of keys that caused all these normally invisible "CR LF" things to appear (apparently they indicate ends of lines). How can I get rid of them?

I use TeXnic Center, and somehow I managed to push some combination of keys that caused all these normally invisible "CR LF" things to appear (apparently they indicate ends of lines). How can I get rid of them?
You've enabled "End of Lines". Disable this by following View > End of Lines:

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