[🐛 Bug]: [dotnet] Webdriver connection gets lost after website closes pop-up window.

[banjand]

Description

We have an older website that we're testing, and we've been having some issues when pages get closed by the website ( when settings are saved and such ). Basically when trying to navigate back to the original window, sometimes the Driver just loses connection and doesn't work anymore ( it'll give an error like this one when trying to switch to another window ).

2026-02-04 18:23:40,117 ERROR EditorialManagerTestLibrary.Automation.Logger - [METHOD: SafeGetWindowHandles - Line 823 in /githubrunner/_work/editorialmanager-test-automation/editorialmanager-test-automation/EditorialManagerTest/Automation/Browsers.cs] Failed to get window handles, driver connection may be lost: An unknown exception was encountered sending an HTTP request to the remote WebDriver server for URL http://localhost:33035/session/01b33f5d6d060cb5c70cc7a028052492/window/handles. The exception message was: Cannot assign requested address (localhost:33035)

Reproducible Code

call
driver.WindowHandles

right after a pop-up window closes (without it being closed by the driver, rather be closed by the website itself)

Debugging Logs

2026-02-04 18:23:40,117 ERROR EditorialManagerTestLibrary.Automation.Logger - [METHOD: SafeGetWindowHandles - Line 823 in /githubrunner/_work/editorialmanager-test-automation/editorialmanager-test-automation/EditorialManagerTest/Automation/Browsers.cs] Failed to get window handles, driver connection may be lost: An unknown exception was encountered sending an HTTP request to the remote WebDriver server for URL http://localhost:33035/session/01b33f5d6d060cb5c70cc7a028052492/window/handles. The exception message was: Cannot assign requested address (localhost:33035)

[selenium-ci]

@banjand, thank you for creating this issue. We will troubleshoot it as soon as we can.

Selenium Triage Team: remember to follow the Triage Guide

[selenium-ci]

Hi, @banjand.
Please follow the issue template; we need more information to reproduce the issue.

Either a complete code snippet and URL/HTML (if more than one file is needed, provide a GitHub repo and instructions to run the code), the specific versions used, or a more detailed description to help us understand the issue.

Note: If you cannot share your code and URL/HTML, any complete code snippet and URL/HTML that reproduces the issue is good enough.

Reply to this issue when all information is provided. Thank you.

[cgoldberg]

Please follow the issue template; we need more information to reproduce the issue.

which browser are you using? browser/driver version? local or remote webdriver? selenium version?

[banjand]

Please follow the issue template; we need more information to reproduce the issue.

which browser are you using? browser/driver version? local or remote webdriver? selenium version?

Chrome - 144.0.7559.96
chromedriverversion 144.0.7559.133
selenium 4.40
local webdriver

[selenium-ci]

We need more information about this issue in order to troubleshoot.

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