System.InvalidOperationException: TypeError: this.tabModal is null

[kwilson-93]

System

• Version: 0.24.0
• Platform: Win 7
• Firefox: 67.0.1
• Selenium: 3.4.0
• Programming Language: C#

Issue

We have some automation tests which are failing with Firefox v67+ only (worked in previous versions e.g. v66.0.5).
The issue occurs when we browse to a page that displays a Windows Authentication prompt (note the issue does not occur if a Windows Authentication prompt is not displayed during the test).
We enter our credentials and hit enter (using SendKeys.SendWait()) which successfully logs in.
But any interaction with the driver object here after results in the following exception being thrown:

System.InvalidOperationException: TypeError: this.tabModal is null

[whimboo]

Could you please attach a trace-level log from geckodriver? Read more about reporting actionable bugs in our contribution guidelines.

[kwilson-93]

hi whimboo,

For whatever reason I cannot generate a trace-level log when I follow the instructions you sent.
The stdout is empty.

[whimboo]

Did you only run those lines or your whole test? It shouldn't be empty.

[kwilson-93]

I ran the whole test till failiure :)
I've repro'd both issues with a simple project.
Open the project, edit URL (must display the "Authentication Required" prompt when browsed), Username and Password respectively within TestMethod1, and run the test method.

I've made it available to you (I hope !!):
https://github.com/kwilson-93/TestingSolution/invitations

[whimboo]

If you could open up (means make it public) the simple project, that would be great. Thanks

[kwilson-93]

@whimboo Done :)

[xTaZzGithub]

I have the exact same issue. For me it was possible to attach a trace-level log to the geckodriver. The output was:

1560416864553 webdriver::server DEBUG -> POST /session/c51a3e2c-6880-452c-840f-c7a42dec4abd/execute/sync {"script":"return document.readyState","args":[]}

1560416864557 webdriver::server DEBUG <- 500 Internal Server Error {"value":{"error":"unknown error","message":"TypeError: this.tabModal is null","stacktrace":"get ui@chrome://marionette/content/modal.js:159:5\nGeckoDriver.prototype._handleUserPrompts@chrome://marionette/content/driver.js:3256:23\nGeckoDriver.prototype.execute_@chrome://marionette/content/driver.js:991:14\nGeckoDriver.prototype.executeScript@chrome://marionette/content/driver.js:911:29\ndespatch@chrome://marionette/content/server.js:289:40\nexecute@chrome://marionette/content/server.js:262:16\nonPacket/<@chrome://marionette/content/server.js:235:20\nonPacket@chrome://marionette/content/server.js:236:9\n_onJSONObjectReady/<@chrome://marionette/content/transport.js:492:20\n"}}

[whimboo]

Do you have a screenshot, so that I know which kind of dialog that is? Maybe you also have a minimized testcase which I could use to reproduce myself?

[kwilson-93]

Thanks @xTaZzGithub !

@whimboo here's the dialog:

[xTaZzGithub]

I'm using this site as a test site : 'https://jigsaw.w3.org/HTTP/Basic/' but it's the same for every other site that request a Basic Authentication.
The dialog looks as follows:

The test case is to open the page, perform the login and then perform any actions with the driver.

[andreastt]

That is not a Windows authentication prompt, but an HTTP Basic Auth prompt from Firefox. WebDriver doesn’t support basic auth yet (tracked in w3c/webdriver#385), so I don’t understand how this could’ve worked in in Firefox 66.

@kwilson-93 Did something change in your test environment/application?

[kwilson-93]

hi @andreastt , I've just verified a test with v66.0.5 of Firefox and it is the same prompt shown above that is displayed. The issue does actually replicate, apologies but I made a mistake saying this version number. I'm unsure what the last version of Firefox was when the issue did not reproduce with, but it is somewhere between v65 & v66.0.5.

The only difference in the whole scenario is the version of Firefox :) Definitely when using v67+ I can reproduce the issue. Note that we're handling the prompt inputs and confirmation by calling SendKeys.SendWait(), not a WebDriver action.

@xTaZzGithub do you experience the same? What version of Firefox are you using when you cannot reproduce the issue?

[andreastt]

Without knowing what SendKeys.SendWait() does by looking at a trace-level log it’s hard to say anything about what circumstances might have changed (it could be a change in basic auth/site origin behaviour in Firefox, in the Marionette server related to keyboard interaction, or in both).

Since HTTP basic auth is not officially supported by WebDriver, I’m inclined to close this on the grounds that we don’t know what the correct behaviour should be. It’s unfortunate that there has been a regression with geckodriver, but again, without more data it’s near impossible to tell.

[whimboo]

This should have actually been fixed by https://bugzilla.mozilla.org/show_bug.cgi?id=1538782 for Firefox 68 which is currently in beta.

[kwilson-93]

hi @whimboo @xTaZzGithub, v68 of Firefox has now resolved this issue for me. Thanks for your help !

[lock]

This issue has been automatically locked since there has not been any recent activity after it was closed. If you have run into an issue you think is related, please open a new issue.