Magento 2.3.5 included another module Magento_Csp which underpins CSP (Content Security Policies (CSP) headers and gives approaches to design them. These approaches can be arranged for adminhtml and frontend zones independently.

There is mention all the things related to CSP on Magento Officially Blog page like Here 

But still, We face issue to integrate it in our latest version. So, No worry that I even have already a solution for that. you only got to add module which I created and solve your problems.

Here is that the link for that: https://github.com/Anantkprajapati/AKP_CSP/

Use the following steps to install the module:

• Step 1: Please download the module from GitHub
• Step 2 : Upload it on <magento_installation>/app/code/AKP/CSP/
• Step 3: After Upload module please change the URL from below files

<magento_installation>app/code/AKP/CSP/etc/config.xml

Replace Below Code

<report_uri>http://www.example.com/</report_uri>

To

<report_uri>YOUR_SITE_URL</report_uri>

• Step 4: After the change URL, Please run below commands

php bin/magento setup:upgrade

php bin/magento setup:static-content:deploy -f

php bin/magento setup:di:compile (if site on production mode)

php bin/magento cache:flush

Now, Please check on the front-end and you’ll see the errors are has gone currently.

Anant

Sr. Full Stack Magento Developer, Passionate Magento Specialist, Magento Certified Developer. He is an expert in PHP and Magento. “To learn something new then take challenges” this is my motive.