Kendall Weaver

Comment Roles is a very simple plugin. The sole purpose is to provide users with the ability to filter comments based on the role of users who have contributed comments to any given post. This plugin is not meant to be used simply as is. Rather it’s expected that a site administrator will apply additional CSS rules to their child theme or to the CSS section of their theme or another plugin in order to to best integrate this plugin in their site. There is currently no additional functionality associated with this plugin.
This plugin does not work with Jetpack Comments. At present there are no plans to try and make it work with Jetpack based on how it functions. Perhaps this will change in the future, but for now I don’t anticipate anything different. 
Additionally, this plugin requires the permalink structure be changed from the default. Any other permalink structure will work fine.

Comment Roles

Allows filering of comments by user role. It adds checkboxes for each role above the comments allowing users to determing which comments to show.

irenem

A simple tool that allows you to switch between user accounts without the hassle of logging in/out. It allows you to view, review and do what yours does to your site.
<h4>Features</h4>
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Switch between user account and to guest user.
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Inherit all capabilities of the selected account, as if you are that very same user.
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Helpful for developers, designers, and site owners.
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</ul>

User Switcher

This plugin helps me very much when I need to test custom user roles.

I like it

This is really helpful plugin for testing my user's issue with my site. When I have only admin account I can easily switch to a random users and reproduce their issue. Thanks for the great solution.

Perfect tool for testing users issue

A helper tool to help you switch between user account without logging in and out.

Comment Roles vs User Switcher