Hi Peppermint Squirrel,
Welcome to Microsoft Community.
Based on the original description, we understand that your device appears to be experiencing unusual advertising behavior in the browser.
Some services(for example, Microsoft Start) may provide advertising information, but browsers themselves are not usually equipped to automatically and actively play advertisements.
In Microsoft Edge Version 127.0.2651.105, we were unable to reproduce the problem.
Generally, when visiting Youtube or similar sites in a new Microsoft Edge, the browser mainly play the marketing ads provided by the site itself, and will be able to play the original video content after the ads.
If possible, would you mind sharing more information about this issue with us?
- Which version of the Microsoft Edge is running on your device?
- What type of ads do you observe? Are they taking up the entire browser page? Or from the same provider? Or some other type?
- Is it the same if you reset the browser itself and then reassign a fresh (without any Microsoft account and without any extensions) browser profile?
What to do if Microsoft Edge isn't working - Microsoft SupportDisclaimer: Your browser automatically saves temporary internet files to help pages load faster. Clearing this cache will sometimes fix website issues. Please back up all your personal files first, such as Favorites, to ensure you do not lose data. - Is it the same if you use a different version of Microsoft Edge? For example, Microsoft Edge Insider. Become a Microsoft Edge Insider | Microsoft Edge
- Is the situation the same when you observe it in a relatively clean environment (for example, new local account, clean boot)? Create a local user or administrator account in Windows - Microsoft Support
Clean Boot starts Windows with a minimal set of drivers and startup programs. It can be used to determine whether a background service or program is interfering or causing a problem. These steps of "clean boot" might look complicated at first glance. However, to avoid any trouble for you, please follow them in order and step-by-step. Please be careful not to disable any services that may be related to security credentials or security authentication, such as TPM, Security, Credential.
If I misunderstand your situation, feel free to correct me and share the information.
Best Regards,
Kyo.Y - MSFT | Microsoft Community Technical Support