Some updates or fixes may not be properly reflected on your side until your browser's cache is emptied, as temporary cache files may overlap with the new files. Follow those steps, depending on the browser you use, to solve the problem.
Google Chrome
From the official Chrome's documentation.
On your computer, open Chrome.
At the top right, click More (the three lined points icon).
Click More tools, then Clear browsing data.
At the top, choose a time range. To delete everything, select All time.
Next to "Cookies and other site data" and "Cached images and files", check the boxes.
Click Clear data.
To make sure everything works well, close all of your Chrome instances and reopen Chrome fresh to reconnect to the platform properly.
Mozilla Firefox
From the official Firefox's documentation.
Click the menu button (the burger) and select Settings.
Select the Privacy & Security panel.
In the Cookies and Site Data section, click Clear Data....
Remove the check mark in front of Cookies and Site Data.
With Cached Web Content check marked, click the Clear button.
Close the about:preferences page. Any changes you've made will automatically be saved.
To make sure everything works well, close all of your Firefox instances and reopen Firefox fresh to reconnect to the platform properly.
Know issues fixed by a cache clearing
Impossible to connect to the platform, "username not found".
Support chat's widget not loading properly.