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When accessing SO with a bookmark that has a list of tags separated by or, for instance:

When logging in from this URL, the browser ends up redirected to

Before logging in

After logging in, the URL the browser gets redirected to is, which obviously isn't a very popular tag.

after logging in This is Firefox 13.0.1, by the way.


Further testing reveals that whitespace or %20 get encoded to + when pressing the login button, and that + gets ignored when decoding the url to redirect to after the login.

But, if the initial URL contains + instead of whitespace or %20, the url when logging in contains the tags separated by %2b. They get decoded correctly to + when redirecting after the login so it works properly if the tags in the URL are separated by +.

Such a pity Firefox decodes + and %2B to whitespace when used in a bookmark.

share|improve this question
Just you wait! Some day, the htmlorjavascript tag will be the most popular on SO, and you'll be sorry you mocked it! – animuson Jun 22 '12 at 8:48
Just encountered same issue - after login the URL I was returned to had %20 and * characters removed. However, this is with Chromium, not Firefox. – Peter Boughton Jan 14 '13 at 22:41
up vote 4 down vote accepted

This was an issue of overly aggressive URL sanitization. Fixed in the next build.

share|improve this answer
Not fixed according to this new report and I just reproduced it myself. – Shadow Wizard May 28 '13 at 10:14
@ShaWizDowArd It seems fixed at least for URL's not including + signs. Works fine for html%20or%20javascript and html+or+javascript as of now. Didn't try using + and other characters though. – Xavi López May 28 '13 at 10:28
@XaviLópez I see. Still, the fix is not complete as there are plenty of tags containing the + character. – Shadow Wizard May 28 '13 at 11:37
@ShaWizDowArd looks like this was an issue of the ' ' character not being encoded and decoded the same way, and in order for tags to be parsed correctly, spaces need to be preserved and not converted to a +. Should be fixed in the next build. – Ben Collins Jun 11 '13 at 18:26
@Ben thanks! :) – Shadow Wizard Jun 11 '13 at 21:10

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