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

# In the Status Bar > Accessibility, check Highlight Text Caret, which enables the Caret Browsing extension. 
# Caret appears in the extensions list and it is yellow indicating that it is on
# In Status Bar > Accessibility, uncheck the Highlight Text Caret 
Expected: caret browsing turns off
Actual: nothing happens 

# Keep the extension installed 
# In Settings > Manage Accessibility Features, check and uncheck "Highlight the text caret when it appears or moves" 
Expected: caret browsing extension turns off and on 
Actual: State is not toggled 

# Remove Caret Browsing extension from Chrome by right clicking on the icon and selecting remove
# Go back to Settings > Manage Accessibility Features, check and uncheck "Highlight the text caret when it appears or moves" 
Note that this does not enable to Caret Browsing extension but instead puts in a purple highlight ring around the caret that turns off and on as expected.