Beta sites contain the following CSS:


For people using the non-mobile interface, it appears that the B and STRONG tags can be used more or less interchangeably, and that the same is true for I and EM. However, in the mobile site CSS, only the latter of each pair is styled—only EM and STRONG work.

If you use the B or I tags they silently fail for users on the mobile site.

This wouldn't be a problem if people didn't use these tags, but they do. Why?

Because of a long-standing bug, the Markdown engine doesn't handle bold or italics correctly with Chinese or Japanese, and users often insert HTML as a workaround. But while Markdown turns stars into EM and STRONG tags, users adding HTML by hand often assume they can use the B and I tags instead. After all, they're easier to type and it looks like they work!

And since it appears to work on the full site, these users may never know there's a problem on mobile.

This problem doesn't just come up on Chinese and Japanese, either. People don't just use HTML as a workaround—they use it as a first resort. Over on ELL meta, a user recently argued that the I tag is to be preferred to EM. And it's easy to find real examples of posts on ELL using those tags. In fact, even Stack Exchange employees recommend using the B and I tags.

Take a look at these screen shots:

  1. Full site:

    full site screen shot

  2. Mobile site:

    mobile site screen shot

You can see this for yourself over on the Japanese meta, if you like. As far as I can tell, it doesn't matter which browser you use. Click back and forth between the full and mobile sites to see the difference.


This has been fixed and will be available in the next deployment (rev 2251 on meta and rev 1609 on the network).

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