Brett

Every once in awhile you want the tabindex to follow a different pattern than the default order. This plugin allows you to set the tabindex for each field, so you can control the tabbing behavior of your forms.
Javascript & jQuery are required.

Gravity Forms – Tab Index

Gravity Forms Add On.  Adds custom tabindex field to the "Advanced" tab for form fields.

Forge12 Interactive GmbH

This plugin will track the load time of each plugin, javascript and css file 
to help you optimizing the performance of your WordPress site. It will help you 
to figure out which plugin / resource causing the slowness of your page.
Track time for:
<ol>
<li>Core</li>
<li>Theme </li>
<li>Plugins</li>
<li>Resources (JavaScript, CSS)</li>
<li>External files</li>
</ol>

F12-Profiler

Excellent! After P3 doesn’t work with PHP7+ anymore, F12 seems finally the one stepping in to fill that gap.

Update [18-Jun-19]. After some small contributions of mine to the dev efforts, the plugin developer has decided to add me to the team, long after this review was written.

Finally an alternative to P3

Trace the execution time of plugins, themes and core files to find the bottlenecks of your system.

Gravity Forms – Tab Index vs F12-Profiler