Should You Install Plugins Not Tested With Your WordPress Version?

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Support » Plugin: Simple Page Sidebars » Warning: This plugin has not been tested with your current version of WordPress.
Is it Okay to Install WordPress Plugins Never Tested with Your Current Version?
WordPress provides the largest repository of free and open source plugins within the WordPress Plugin Repository. When an author of a plugin submits it to the repository, they have to submit a “readme” file. This file is used by the plugin directory to create the page for the plugin. It will also include a “tested up to” tag, which will display in the information for the plugin testing.
Blogging Tips – 17 Essential Free WordPress Plugins to Create a Powerful Blog
Do not be overwhelmed with the number of plugins you will encounter while creating a WordPress blog. These handful WordPress plugins I featured here are all that you need to built a powerful blog. Take the time to explore each one and see how it can work best with your blog. These recommendations are tried and tested and even professional bloggers use them on their own blogs to make the job a tad easier by supercharging your blog with these plugins. However, there are few considerations to think about. Make sure to test the plugin first, whether it’s compatible with your version of WordPress and the WordPress theme you used.
This Tool Lets You Test WordPress Plugins Without Installing It
If you don’t want to install new WP setups just to test different plugins you’ll love Addendio. It’s a free tool for WordPress users that lets you try thousands of plugins for free through an online web app.
WordPress Plugin FAQs and Troubleshooting Guide
This is not something controlled by Leadpages—you will need to find the plugin or script on your site that is causing this and disable it to resolve the issue. To find the plugin that may be causing this, you can deactivate any plugins you know you’re not using. If you continue to encounter the issue, we recommend deactivating each plugin on your site one at a time to narrow down the one that is causing the issue.