Intermittent ReadTimeoutError (HTTPConnectionPool localhost) during long SeleniumLibrary execution with Chrome freezing

Hi,

We are experiencing intermittent ReadTimeoutError failures during long Robot Framework executions using SeleniumLibrary.

The issue is difficult to reproduce consistently, but it occurs frequently during large execution batches.

Environment

• Robot Framework: Robot Framework 7.3.2 (Python 3.12.0 on win32)
• SeleniumLibrary: 6.8.0
• Selenium: 4.36.0
• Chrome: 149.0.7827.200 (64-bit)
• Windows 11

Error

ReadTimeoutError:
HTTPConnectionPool(host='localhost', port=xxxxx):
Read timed out. (read timeout=120)

Sometimes we also see:

Timed out receiving message from renderer

Behavior

The browser visibly freezes when this happens.

The failure is intermittent and can occur in different Selenium keywords, for example:

• Click Element
• Wait Until Element Is Visible
• Wait Until Page Loaded
• Set Selenium Page Load Timeout

It most commonly happens during:

• Logout
• Navigating to the Browse module after switching back to the main window

However, it is not limited to those locations. The same timeout can occur in different tests at different steps.

Additional observations

• A new browser is launched for every test case.
• Failures are random and not tied to one specific test.
• The application is still running, but Chrome becomes unresponsive.
• Selenium waits for approximately 120 seconds before raising the ReadTimeoutError.

##Log excerpt

Wait Until Page Loaded  00:10:00.795KEYWORD 02_Browse_POM . Click On the Browse Module   Start / End / Elapsed: | 20260706 15:04:20.439 / 20260706 15:14:21.234 / 00:10:00.795 -- | --

Question

Has anyone experienced similar intermittent browser freezes resulting in HTTPConnectionPool(host='localhost') ReadTimeoutError?

Is this known to be related to SeleniumLibrary, Selenium Python, ChromeDriver, Chrome, or is there anything we should investigate further?

Any suggestions would be greatly appreciated.

Beginne mit den gemeldeten SeleniumLibrary-Schlüsselwort-Einstiegspunkten—Click Element, Wait Until Element Is Visible, Wait Until Page Loaded und Set Selenium Page Load Timeout—und reproduziere das Verhalten unter den aufgeführten Versionen. Vergleiche den fehlschlagenden Logout und die Navigation des Browse-Moduls mit einem minimalen Langzeitfall und sammle Chrome/Selenium-Timeout-Logs; abgeschlossen ist die Untersuchung, wenn ein reproduzierbarer Bibliotheksfehler isoliert oder dokumentiert wurde, dass die Ursache umgebungsbedingt oder upstream ist.