Please re-run Magento compile command
What is Magento Compilation?
The Magento Compilation is a feature that allows you to compile all Magento installation files (source code, including plugins) into a single folder in order to create a single include path. This feature is designed to improve the performance of your online store and is supposed to give between 25% and 50% increase in your page load speed.
If compilation is turned on in Magento, whenever there’s a change of source in the root folder, you need to re-run the compilation process for that change to be applied on your website.
“Please re-run Magento compile command” message
This is a system message that appears whenever there’s a change in Magento source. Every time the upgrade command is finished, you’ll see this message.
To run the compile command, type this line:
php bin/magento setup:di:compile
In Magento 2, if you already disable compilation or are working in dev-mode, you can ignore this message.
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