Changing insertion point to always insert at root block

[ehausen]

I trying to build a system where all patterns are pre-built as elements that should be inserted at page root level. They are basically top level page rows with content.

So I would like to always insert elements at BlockRootClient even if user has selected/clicked somewhere deeper inside than one the outermost one rows.

When the Pattern Explorer modal is open I can run following in the console and it select the insertion point I want:

const ed = wp.data.select('core/block-editor');
wp.data.dispatch('core/block-editor').selectBlock( ed.getBlockHierarchyRootClientId( ed.getSelectedBlockClientIds() ) );

And a selection moved "out" for example:
Page > Row > Section > Paragraph --> Page > Row

But when I tried to hack it to run on a subscribe, like so, the modal closes:

Not working. Modal closes.

wp.data.subscribe( () => { 
    const PatternModal = document.getElementsByClassName("components-modal__frame block-pattern-explorer__modal is-full-screen")[0];    
    //const spinner = document.getElementsByClassName("components-modal__frame block-pattern-explorer__modal is-full-screen .components-spinner")[0]
    const ed = wp.data.select('core/block-editor');
    const numOfParentsBlocks = ed.getBlockParents(ed.getSelectedBlockClientId()).length;
    if(PatternModal && numOfParentsBlocks > 0 ) {  
        console.log("Pattern Modal exist! And number of parents is > 1");
        wp.data.dispatch('core/block-editor').selectBlock( ed.getBlockHierarchyRootClientId( ed.getSelectedBlockClientIds() ) );
    } 

});

I also tried modifying use-insertion-point.js slightly, like so:
const selectedBlockClientId = getBlockRootClientId( getSelectedBlockClientId() );

But got some strange results.

I clearly don't grasp the principles very well.
Could you perhaps point me in the right direction?