So as you probably know, some of our tests that pass in Firefox fail in Chrome.
One issue is that in a number of places the tests accept a string to look for in a URL that is defined as "Main Page". But in the browser, the URL ultimately will contain the string "Main_Page".
I committed a change such that the test would check that *at some point* the URL will contain the string "Main Page" as specified in the test. In hindsight, this was probably a bad idea, because the original tests just care that we land on the correct URL, not that we handle spaces correctly. https://gerrit.wikimedia.org/r/#/c/119878
Jon committed a change that invisibly munges the input string to replace the first (and only the first) space character with an underline character. This is probably also not a great idea, because it secretly changes test inputs without the user (or maintainer) knowing. https://gerrit.wikimedia.org/r/#/c/120564
After thinking it over, I think what we should do to make the tests perform the way the tests were intended to perform is to revert the two changes I mentioned above, and to simply change every occurrence of "Main Page" in the features to be "Main_Page". That will not only satisfy Firefox and Chrome, but it will also satisfy the intent of the tests themselves. I suspect that using "Main Page" was essentially a typo that propagated through the test suite over time.
-Chris