Yii2: How to process content after rendering by controllers but before showing to user?

Question

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Good afternoon! Can you please tell me how to process all content after rendering by controllers and before showing it to the user?

Those. the task such, is a certain value in base which changes periodically. It is necessary that after the content is rendered but before being shown to the user, change some substring "[replace]" in it and replace it with the value then.

for example, 1c-bitrix has the following event:
AddEventHandler("main", "OnEndBufferContent", "ChangeMyContent");
here a function is called that processes $content and returns it to the output

, or if in self-written code, the usual methods:
ob_start();
....
code
.....
$out = ob_get_clean();
echo str_Replace('','',$out);

and how to implement it correctly here in Yii2?

The implementation is needed either globally or at the controller level, both are possible.
Thanks in advance!