Editing strings with exponents, potential bug

Bug introduced in 8.0. or earlier, persisting through 11.0.1.

I know this site is not fond of screenshots, but this is the only way I could think of to communicate this behavior. When editing expressions that contain strings with exponents, such as Quantity expressions, the exponents can disappear.

This has been sent to Wolfram as a bug report but not yet confirmed. As mentioned in the screenshot, the workaround is to not attempt typeset exponents, just use the carat ^

This question earned me a "tumbleweed" badge, so I am answering it just to close it out. The behavior was reproduced by Wolfram tech support, but I did not get a follow-up from a developer. My workaround is to avoid typeset exponents in Quantity unit expressions.