You can add the following to advancedsettings.xml…
<loglevel hide="true">1</loglevel>
This will make debug logging persistent without the screen overlay.
Please note that this setting is something you will want to remove once your done testing as it needlessly increases writes under normal use. There is also a limit to the size of logs that can be uploaded so you may want to reboot twice at the start of your viewing sessions just to keep the size of the log down.