1473638 - :screenshot --fullpage fails silently in about:license

Status: RESOLVED DUPLICATE of bug 766661

(DevTools :: Console, defect, P3)

Description

[Nicolas Chevobbe [:nchevobbe]]

**Steps to reproduce**
1. Go to `about:license`
2. Evaluate `:screenshot --fullpage`

**Expected results**

I get a notification that the screenshot was saved.

**Actual results**

There's nothing displayed in the console, and the file isn't downloaded in the Download folder.
There's the following error in the browser console: 

evaluateJSAsync threw an exception: Error: Encountered error while waiting for Helper Result: [Exception... "Failure"  nsresult: "0x80004005 (NS_ERROR_FAILURE)"  location: "JS frame :: resource://devtools/shared/base-loader.js -> resource://devtools/server/actors/webconsole/screenshot.js :: createScreenshotData :: line 95"  data: no]
Stack: evaluateJSAsync/<@resource://devtools/shared/base-loader.js -> resource://devtools/server/actors/webconsole.js:906:9
MessageListener.receiveMessage*_addListener@resource://devtools/shared/base-loader.js -> resource://devtools/shared/transport/transport.js:709:7
ready@resource://devtools/shared/base-loader.js -> resource://devtools/shared/transport/transport.js:726:7
_onConnection@resource://devtools/shared/base-loader.js -> resource://devtools/server/main.js:1201:5
connectToParent@resource://devtools/shared/base-loader.js -> resource://devtools/server/main.js:683:12
onConnect</<@resource://devtools/server/startup/frame.js:49:22
onConnect<@resource://devtools/server/startup/frame.js:48:7
exports.makeInfallible/<@resource://devtools/shared/base-loader.js -> resource://devtools/shared/ThreadSafeDevToolsUtils.js:109:14
MessageListener.receiveMessage*@resource://devtools/server/startup/frame.js:71:5
@resource://devtools/server/startup/frame.js:19:4
connectToFrame/<@resource://devtools/shared/base-loader.js -> resource://devtools/server/main.js:987:7
connectToFrame@resource://devtools/shared/base-loader.js -> resource://devtools/server/main.js:983:12
connect@resource://devtools/shared/base-loader.js -> resource://devtools/server/actors/targets/frame-proxy.js:49:21
async*BrowserTabList.prototype._getActorForBrowser@resource://devtools/shared/base-loader.js -> resource://devtools/server/actors/webbrowser.js:323:10
BrowserTabList.prototype.getTab@resource://devtools/shared/base-loader.js -> resource://devtools/server/actors/webbrowser.js:342:16
onGetTab@resource://devtools/shared/base-loader.js -> resource://devtools/server/actors/root.js:332:27
Async*onPacket@resource://devtools/shared/base-loader.js -> resource://devtools/server/main.js:1783:15
send/<@resource://devtools/shared/base-loader.js -> resource://devtools/shared/transport/transport.js:553:13
exports.makeInfallible/<@resource://devtools/shared/base-loader.js -> resource://devtools/shared/ThreadSafeDevToolsUtils.js:109:14
exports.makeInfallible/<@resource://devtools/shared/base-loader.js -> resource://devtools/shared/ThreadSafeDevToolsUtils.js:109:14
Line: 906, column: 9

Comment 1

[Nicolas Chevobbe [:nchevobbe]]

Note that `:screenshot` alone works fine.

Comment 2

[Nicolas Chevobbe [:nchevobbe]]

Seems triggered by this line: https://searchfox.org/mozilla-central/rev/6ef785903fee6c0b16a1eab79d722373d940fd78/devtools/server/actors/webconsole/screenshot.js#95

Comment 3

[J. Ryan Stinnett [:jryans] (Use needinfo, replies may be slow)]

This seems like bug 766661.  Screenshots currently fail for long pages, like about:license in full page mode.