function filterQ2LayoutJSON( contentFilename ){
        let file = filesWithMetadata[contentFilename]
        if (!file) return
	// can be removed for URLs as those are not with metadata

        let contentType = file.contentType

	// mereology option
	let openingOptions = filesWithMetadata[contentFilename].openingOptions
	// can be used via e.g. showFile("https://fabien.benetou.fr/?action=source",{ mereology:"whole"})

	// filtering, only applying what's next to a certain content type and/or with filename filtering with .startsWith() .endsWith() .includes() or regex
        if ( contentType.includes("json") && contentFilename.endsWith("_q2layout.json") ) {
                console.log('it is a Q2 Layout JSON file', contentFilename)

		fetch( contentFilename ).then( r => r.json() ).then( savedDataFromPreviousSession => {
			// console.log( savedDataFromPreviousSession )
			savedDataFromPreviousSession.map( savedData => 
				Array.from( document.querySelectorAll('.'+classNameItemsToSave) )
				.filter( noteEl => noteEl.getAttribute("value") == savedData.value )
				// search by value as in theory those are constant (but not necessarily unique, even though usually are)
				.map( foundNoteEl => {
					foundNoteEl.setAttribute("position", AFRAME.utils.coordinates.stringify(savedData.position) )
					foundNoteEl.setAttribute("rotation", AFRAME.utils.coordinates.stringify(savedData.rotation) )
				} )
				// should also debug the unfound ones
			)

			AFRAME.scenes[0].emit('q2layoutjsonloaded', contentFilename)
			// to use the event consider :
			//AFRAME.scenes[0].addEventListener("templateexampleloaded", e => console.log(e))

		} ); 
	}
        applyNextFilter( contentFilename )
	// can stop here or move on to the next filter that might or not be applied
}
sequentialFilters.push( filterQ2LayoutJSON )
// adding this to the list of filters to go through, order matters
	// typically one would be generic filters first then more specific ones after