Legendary Silke
[I][B]You like dragons?[/B][/I]
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- Seen Dec 23, 2021
...and serve up different content to users of Internet Explorer. Invalid content for Internet Explorer 8 and newer.
I went into this forum and also Victory Road as usual, but I was having fun messing around with my user agent string. Probably to test how sites react to my spoofed user agent string...
This is how Victory Road, a vBulletin 3 forum, looks before I changed the user agent string. Notice the Last Post info box - the last two lines became one line. This is not the expected behaviour - Firefox, Chrome and Opera show all three lines. It's caused by the vBulletin software serving up code that's right for Internet Explorer 7 and older, not knowing that Internet Explorer 8 and newer doesn't have an issue with that... and break it instead.
This is the same thing in PokéCommunity. (If you were wondering how I got box-shadow to work in Snivy's Holiday, well, I intercepted the request to the original CSS and instead made it load my copy of the same style's CSS, with the unprefixed box-shadow inserted. Fiddler2 can be a powerful tool to debug pages.)
And let's see what happens when I change my user agent string to one of Firefox 9...
That's a big difference! There is a good reason why user agent sniffing and serving different content by it is not a good idea. Browsers can and will get bugs fixed - never assume that it'll never change!
This MSDN blog post, "The Perils of User-Agent Sniffing, 2011 Edition" should help a lot in understanding the issue.
I went into this forum and also Victory Road as usual, but I was having fun messing around with my user agent string. Probably to test how sites react to my spoofed user agent string...
Spoiler:
This is how Victory Road, a vBulletin 3 forum, looks before I changed the user agent string. Notice the Last Post info box - the last two lines became one line. This is not the expected behaviour - Firefox, Chrome and Opera show all three lines. It's caused by the vBulletin software serving up code that's right for Internet Explorer 7 and older, not knowing that Internet Explorer 8 and newer doesn't have an issue with that... and break it instead.
Spoiler:
This is the same thing in PokéCommunity. (If you were wondering how I got box-shadow to work in Snivy's Holiday, well, I intercepted the request to the original CSS and instead made it load my copy of the same style's CSS, with the unprefixed box-shadow inserted. Fiddler2 can be a powerful tool to debug pages.)
Spoiler:
And let's see what happens when I change my user agent string to one of Firefox 9...
Spoiler:
That's a big difference! There is a good reason why user agent sniffing and serving different content by it is not a good idea. Browsers can and will get bugs fixed - never assume that it'll never change!
This MSDN blog post, "The Perils of User-Agent Sniffing, 2011 Edition" should help a lot in understanding the issue.