#4942 (ok 4.4.9) Export to gzip saves plain text under Chrome

[George Nikolov]

Steps to recreate:
- go to any database
- click 'Export' tab
- select 'Custom'
- select 'gzipped' from 'Compression'
- press 'Go'

Under:
- Chrome 43.0.2357.81 m - the file is saved as plain text, wrong
- Firefox 38.0.5 - the file is saved az gzipped data, properly
- Opera 29.0.1795.60 - the same as Firefox

OS: Win7 Pro SP1

[Marc Delisle]

Confirmed: phpMyAdmin 4.4.8, Windows 8, Chrome 43. In the same environment, behavior is OK under Firefox.

[Madhura Jayaratne]

https://github.com/phpmyadmin/phpmyadmin/blob/347dc70c18aa4d036821db3ea379068b338952d8/libraries/core.lib.php#L710...L714 seems to be the cause of the bug.
However, these lines have been added to fix a related bug https://github.com/phpmyadmin/phpmyadmin/commit/ccd65816b8420b5e5239537bb110185d7ac2cace

[Madhura Jayaratne]

According to https://code.google.com/p/chromium/issues/detail?id=268085 Chrome has changed how it behaves in such situations. Its gzip encoding hack has been removed for Chrome 43 and above to be in line with Apache 2.4.

So there is no solution that fits all version of Apache or all version of different browsers. I suggest we change our code in 4.5 to be in line with Chrome 43+ and Apache 2.4, hoping that Fireofx will also adopt a similar behavior.

[Marc Delisle]

It would be more prudent to implement a solution based on each browser and browser version, if possible.

[Madhura Jayaratne]

Fixed with https://github.com/phpmyadmin/phpmyadmin/commit/a39a5ce2656a8a6648985bfbe6ed4aa65ba3b27c