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query string http%3A%2F%2F turns into http%253A%252F%252
Is a slash ("/") equivalent to an encoded slash ("%2F") in the path ...
urlencode - PHP URL encoding method - Stack Overflow
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views - %252F in the URL - Drupal Answers
URL to URI encoding changes a "%3D" to "%253D"
Redirect url being encoded twice · Issue #119 · oakserver/oak
Security email connection - Microsoft Community
URL slash '/' get double encoded. Changed to %252F instead of %2F
in external_browser=0&aunchurl=http%253A%252F%252F er