Firefox stops recognizing Yubikey as a PIV card after it is used externally
Firefox (verison 67.0.4 on Windows 10 x64), though the issue has been going on for probably around a year now) stops recognizing my Yubikey 4 (firmware version 4.3.7) whenever I use the PIV card functionality from an external application. In order to rectify this I need to restart Firefox and re-enter my pin (on a site which requires it). If an external application uses the Yubikey as a PIV card (for example Windows Remote Desktop) the dialog asking for the pin (within Firefox) opens. If the box is closed repeatedly without entering anything in the text field (eg holding down the Esc key) the box re-opens forever. If the something is entered into the box, then there seems to be *a chance* of the box closing and staying closed, but if this happens the box will re-appear whenever any traffic goes between the browser and the site requiring the use of the Yubikey (navigation to a new page, submitting a form etc). This seems to happen regardless of whether or not the input to that dialog is the correct pin for the card, or random text.
The Yubikey is available to Firefox using OpenSC - the card is configured pointing to "C:\Program Files\ OpenSC Project\OpenSC\pkcs11\onepin-opensc-pkcs11.dll". Logging into the Yubikey within the Firefox security devices settings view does not seem to change its behaviour with respect to this issue.
Steps to reproduce: 1. Start Firefox and navigate to a site which requires the use of PIV functionality and enter the correct pin for the card. 2. Start an external application and run it in a way which also requires the PIV functionality of the Yubikey. 3. Go back to Firefox and refresh the page. 4. Enter the correct pin for the card OR mash keyboard. 5. Restarting Firefox will resolve the issue, until another external program which uses the Yubikey as a PIV card is run again.
Additional System Details
- Shockwave Flash 32.0 r0
- User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:67.0) Gecko/20100101 Firefox/67.0