Setting in "content blockers" does not show my adblocker (iPad Pro)

Having installed 1Blocker, you need to enable the corresponding Safari extensions:

Settings > Safari > [General] Extensions - enable all of the 1Blocker extensions

With 1Blocker installed, you don't need Purify. If installed, delete Purify from your iPad before you encounter unexpected behaviour.

As for your issue when posting to ASC - if you see a red warning upon trying to submit a post after signing-in to ASC, just refresh the page. After refreshing the page, you should see a prompt to Continue Draft.

By example:

I cannot envisage the "pulsating, scrolling, twirling" to which you refer.

Try a forced-restart of your iPad - as this will often clear an isolated software issue:

Force restart iPad (models with Face ID or with Touch ID in the top button)

If your iPad doesn’t have the Home button, do the following:

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

Force restart iPad (models with the Home button)

Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

If the problem persists after performing the restart, it may be necessary to reset your iPad settings. While this reset will not cause any loss of data, as a precaution, it is always wise to ensure that you have a current iCloud or iTunes backup before performing the reset:

How to back up your iPhone, iPad, and iPod touch - Apple Support

When you are happy to proceed, you can perform the reset from iPad settings:

Settings > General > Transfer or Reset iPad > Reset > Reset All Settings

If the problem still doesn’t clear, the next step is to reset the iPad to factory settings:

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

Otherwise, you would be best advised to seek assistance directly from Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page. Alternatively and perhaps easier, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:

https://apps.apple.com/app/apple-support/id1130498044

You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians may be able to assist:

Genius Bar Reservation and Apple Support Options - Apple

Which "content blocker" App have you attempted to install on your iPad? With the benefit of more information, contributors here might be better able to offer appropriate help or guidance.

Please also confirm the iPadOS version installed on your iPad; at the time of writing, iPadOS 17.4.1 is current.