Currently I am preparing the text for a paper (together with two coauthors) where we cite help from MO on two occasions. I am doing this using the `cite` button. It works correctly both in Acrobat and SumatraPDF, i. e. leads to the correct place when clicked from inside pdf. However when I do it in the built in gmail pdf viewer, both in latest builds of Chrome and Firefox, it gives a wrong page, although on MO. The reason is that I don't know why but it shaves off the very last symbol of the url. This happens with both links.

I am on Windows 10. Here is one of the two cases; the second produces identical error.

I want to cite the answer https://mathoverflow.net/a/313198. The `cite` link with the amsrefs option produces

    \bib\{313198}{misc}{    
    title={Seeking a more symmetric realization of a configuration of 10 planes, 25 lines and 15 points in projective space},    
    author={Noam D. Elkies (https://mathoverflow.net/users/14830/noam-d-elkies)},    
    note={URL: https://mathoverflow.net/q/313198 (version: 2018-10-19)},    
    eprint={https://mathoverflow.net/q/313198},    
    organization={MathOverflow}  
    }

which I paste as

    \bib{MOElkies}{misc}{
    label={E},
    title={Seeking a more symmetric realization of a configuration of 10 planes, 25 lines and 15 points in projective space},
    author={Noam D. Elkies (https://mathoverflow.net/users/14830/noam-d-elkies)},
    note={URL: https://mathoverflow.net/q/313198 (version: 2018-10-19)},
    eprint={https://mathoverflow.net/q/313198},
    organization={MathOverflow}
    }


into the tex file between `\begin{bibdiv}\begin{biblist}*{labels={shortalphabetic}}` and `\end{biblist}\end{bibdiv}` (along with several other references).

As I said, the url is correct in the Acrobat and SumatraPDF; in the gmail pdf viewer, if I copy the link it is also OK, but if I *click* on it, I am sent to https://mathoverflow.net/q/31319, which is, understandably, an entirely different answer to an entirely different question.

I am not sure whether to use the [tag:bug] tag here, as apparently it is a bug in the gmail pdf viewer, not in the MO system, but I believe still something has to be done about it.

**Update**

Tried to strip it down to an mwe:

    \documentclass{amsart}

    \usepackage{amsrefs}

    \begin{document}

    $\binom nk$

    \begin{biblist}
    \bib{E}{misc}{
    author={Noam D. Elkies (https://mathoverflow.net/users/14830/noam-d-elkies)},
    note={URL: https://mathoverflow.net/q/313198 (version: 2018-10-19)}
}
\end{biblist}
    \end{document} 

Strangely enough, if I omit that `$\binom nk$` or put there anything else, the error does not occur.