_collectBaseTabData@resource:///modules/sessionstore/TabState.jsm💯1 (inner) – Tab state – file access error

Firefox Development
#1

Here, for example:

This operation failed due to a file access error:
browser is undefined(TypeError)

…

_collectBaseTabData@resource:///modules/sessionstore/TabState.jsm:100:1
collect@resource:///modules/sessionstore/TabState.jsm:62:12
collect@resource:///modules/sessionstore/TabState.jsm:31:12
ssi_collectWindowData@resource:///modules/sessionstore/SessionStore.jsm:3196:21
getCurrentState/<@resource:///modules/sessionstore/SessionStore.jsm:3055:11
ssi_forEachBrowserWindow@resource:///modules/sessionstore/SessionStore.jsm:4136:9
getCurrentState@resource:///modules/sessionstore/SessionStore.jsm:3051:7
ssi_getBrowserState@resource:///modules/sessionstore/SessionStore.jsm:2181:17
ss_getBrowserState@resource:///modules/sessionstore/SessionStore.jsm:252:12
getSessionState@chrome://sessionmanager/content/modules/session_data_processing.jsm:61:81
getSessionState@chrome://sessionmanager/content/modules/session_data_processing.jsm:32:10
save@chrome://sessionmanager/content/modules/session_file_io.jsm:262:26
save@chrome://sessionmanager/content/modules/session_file_io.jsm:51:10
sessionPromptCallBack@chrome://sessionmanager/content/modules/session_manager.jsm:558:5
sessionPromptCallBack@chrome://sessionmanager/content/modules/session_manager.jsm:42:10
onAcceptDialog@chrome://sessionmanager/content/session_prompt.js:1235:20
anonymous@chrome://global/content/bindings/dialog.xml line 379 > Function:3:8
_fireButtonEvent@chrome://global/content/bindings/dialog.xml:380:28
_doButtonCommand@chrome://global/content/bindings/dialog.xml:348:28
_handleButtonCommand@chrome://global/content/bindings/dialog.xml:336:18

To troubleshoot the underlying issue(s)

Should I focus first on the uppermost line(s) in the stack?

https://dxr.mozilla.org/mozilla-central/source/browser/components/sessionstore/TabState.jsm#100 I guess …

Cross reference https://mozilla.logbot.info/introduction/20171028#c13759787

#2

I probably no longer need help here.

tl;dr

  • just rarely, Firefox crashes at quit time
  • I have learnt to recognise the symptoms that precede those crash situations
  • the ‘stack’ above was copied from a dialogue of Session Manager, which I do not expect to work when Firefox is expected to crash
  • in IRC thanks to @arai I learnt that execution comes from the bottom.

Re: the innermost line and –

if (browser.audioMuted) {

– prior to learning about bottom-up, in the absence of reproducible steps I wondered whether Sound Control might be contributory to any crash situation. I no longer suspect an issue with Sound Control.

After paying attention to two other extensions, both of which are off-topic from the opening post: I hope to have no more comparable crashes at quit time.