I started playing World of Warcraft a few months ago to get a good feel of modeling and texturing for games and sometimes when I log out of WoW and log into Maya, the same thing happens to me. I haven't tried searching the help files for an answer but I found that restarting my computer always fixes it.
But you could be right, maybe there's a button or button combination that makes it do that.
Don't be satisfied with what you can do but rather strive to do the things you can't do!
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