Chromium-controlled DevTools extension panels (iframes) with de-synced state

[Warren Halderman]

I'm developing an extension for DevTools, but am running into an issue where the two duplicated devtools extension iframes have mismatched UI state (Chromium 142.0.7444.59).

1. This devtools panel (iframe) is displayed, but has an outdated and incorrect UI state.
   #-blink-dev-tools > div.widget.vbox.root-view > div > div:nth-child(1) > div > div.vbox.flex-auto.tabbed-pane.main-tabbed-pane > div > div > div > div > iframe
   
   
2. This devtools panel (iframe) is not displayed, but has an up-to-date and correct UI state:
   #-blink-dev-tools > iframe

What can cause the state between these two duplicated iframes to de-sync?

Less important, but it's been bothering me for a few months now; why are there two seemingly duplicate iframes for the same extension?...

[Warren Halderman]

Never mind about the second question; I hadn't realized that the devtools page in the manifest and the devtools panel were meant to be separate HTML pages.

[Warren Halderman]

Never mind the first question either, turns out I'm a dumbass and my previous misunderstanding was causing issues all along. ☠