I noticed that In Chrome Stable and Canary on Windows, the extension sections are separated by headings, but not in Chrome OS. 

Actually pasting repro steps:
Chrome: 64.0.3270.0 (Official Build) dev (64-bit)
Firmware Version	Google_Samus.6300.174.0

Steps to repro:
# With chromevox running: open the extensions page: alt+f > more tools > extensions
# Tab through all options on the page
# Notice that Chromevox does not announce which extension each button or checkbox controls

Expected: The extension name would be announced along with the control's purpose

Actual: Only the control's purpose is announced

# Explore all controls on the page using search+left and right arrow keys
# Notice that extension names are announced, but it is difficult to know in the middle of the document which set of controls will control a particular extension

Expected: Each extension and it's controls would be separated from the previous and next set

Actual: There is nothing to differentiate one set from another

hello:  heddings are not enough it needs to have a lable that includs the
information if you tab  throu it  needs to stand alone and speak the proper
lable not just remove from chrome but what are  you  removing from  chrome
think of it this way if you bring up the list of buttons in jaws what do
you see you don't see the hedding you see the label only so it should be
formated like this remove x from  chrome and x is the item your  removing

This is a duplicate of Issue 791665