2053274 - Crash when opening DevTools: can't access dead object

Status: RESOLVED DUPLICATE of bug 2042101

(DevTools :: General, defect)

Description

[Roman Deev]

Steps to reproduce:

I just pressed Ctrl + Alt + C. I was debugging a page at the time where an iframe was created from a userscript. I don't think there were any other details.

Error in Inspector Panel:

Error: Protocol error (TypeError): can't access dead object from: server0.conn0.watcher2.process8147//domwalker165 (resource://devtools/server/actors/inspector/event-collector.js:278:21)

Client Packet:

{
  "type": "querySelector",
  "node": "server0.conn0.watcher2.process8147//domnode164",
  "selector": "body",
  "to": "server0.conn0.watcher2.process8147//domwalker165"
}

Server Packet:

{
  "from": "server0.conn0.watcher2.process8147//domwalker165",
  "error": "TypeError",
  "message": "can't access dead object",
  "fileName": "resource://devtools/server/actors/inspector/event-collector.js",
  "lineNumber": 278,
  "columnNumber": 21
}

Server Stack:

getDOMListeners@resource://devtools/server/actors/inspector/event-collector.js:278:21
getListeners@resource://devtools/server/actors/inspector/event-collector.js:340:28
hasListeners@resource://devtools/server/actors/inspector/event-collector.js:226:17
hasEventListeners@resource://devtools/server/actors/inspector/event-collector.js:807:21
hasEventListeners@resource://devtools/server/actors/inspector/node.js:445:43
form@resource://devtools/server/actors/inspector/node.js:239:37
write@resource://devtools/shared/protocol/types.js:374:32
types.addArrayType/write/<@resource://devtools/shared/protocol/types.js:224:33
write@resource://devtools/shared/protocol/types.js:224:16
write@resource://devtools/shared/protocol/types.js:272:39
write@resource://devtools/shared/protocol/Response.js:101:22
write@resource://devtools/shared/protocol/Response.js:49:28
sendReturn@resource://devtools/shared/protocol/Actor.js:258:38

Stacktrace:

onPacket/<@resource://devtools/shared/protocol/Front.js:405:31
DevTools RDP*request@resource://devtools/shared/protocol/Front.js:321:14
generateRequestMethods/</frontProto[name]@resource://devtools/shared/protocol/Front/FrontClassWithSpec.js:94:19
querySelector@resource://devtools/client/fronts/walker.js:150:34
#getDefaultNodeForSelection/defaultNodeSelectors<@resource://devtools/client/inspector/inspector.js:729:20
#getDefaultNodeForSelection@resource://devtools/client/inspector/inspector.js:736:20

Comment 1

[Roman Deev]

Clarification: cmd + alt + C (a hotkey that opens the HTML element picker)

Comment 2

[Roman Deev]

And it looks like I can reproduce it consistently:

1. Install Violentmonkey https://addons.mozilla.org/firefox/addon/violentmonkey
2. Install the userscript https://raw.githubusercontent.com/deevroman/better-osm-org/master/better-osm-org.user.js
3. Open https://www.openstreetmap.org
4. Click on the ViolentMonkey icon
5. Click Settings for the installed userscript (not ViolentMonkey)
6. Press cmd + alt + C
7. Crash

Comment 3

[Roman Deev]

Attachment: demo.mp4