Issues caused by the plugins incompatibility
A plugin conflict is something that occurs when two plugins are incompatible with one another.
For example, when you're having issues with one plugin functioning properly, often the problem is caused by a conflict with another plugin.
Note: Detecting the conflict is very important step to take because the problem can be resolved easily.
The following is known issue you may get when using Shield with other certain plugins.
Shield conflicts with Divi Page Builder Plugin
If you have Shield's Lockdown module enabled and you've used the option "Mask WordPress Version", it can happen that this option conflicts with Divi's Color Picker feature.
This sort of compatibility with that version masking option is to be expected. It can cause quite a bit of interference with plugins that rely on that setting to be accurate.
Important update: "Mask WordPress Version" option is removed in Shield v9.0. So, generally, there is no conflict there.
Elementor Pro wont edit pages unless its in safe mode
If Elementor Pro doesn't edit pages unless its in safe mode, the problem is likely caused by Elementor using iframes and your restrictions break it.
In this case, you will need to review Shield's HTTP Headers settings.
You may go to the Advanced Security Headers => Block iFrames, and then change settings from 'Block All iFrames' to 'On: Allow iFrames On The Same Domain':
Avada Live builder won't load or edit pages
Just like for Elementor, you'll need to change Block iFrames setting in Shield - set to 'On: Allow iFrames On The Same Domain'.