Chrome OS with flag enabled: #enable-experimental-accessibility-features
67.0.3383.0 (Official Build) dev (64-bit)
Google_Samus.6300.276.0

# Enable STS
# Go to mail.google.com and sign in (I tried this with both corp and non-corp accounts)
# Use search key + draw mouse highlight rect around the email preview view in the inbox.
Expected: contents on screen read
Actual: highlight stays in place while first line of email is read including content that is offscreen. It then reads everything again while the highlight moves to the area it is reading.

I suspect there is either an invisible control that's being read or that the checkbox has too much information attached to it. I used ChromeVox to investigate.

ChromeVox also reads offscreen content all the time. It only reads all the information at the beginning of the email when I linear navigate to whatever control is reading out all the info. It doesn't do this when using ChromeVox normally.

See video for repro with ChromeVox and STS: https://drive.google.com/file/d/1kmypnBgc4WjwPRrLmnfmUNQWqBI9bXfB/view