pub-edit-toggle.bookmarklet.js

javascript:/*pub↔edit*/(function (mappings) {
	const currentURL = String(document.location.href);
	const currentHost = document.location.hostname;
	const currentProtocol = (document.location.protocol + '//');
	const gi = '.github.io';
	const gr = /github.com\/([^\/]+)\/\1.github.io\/edit\/([^\/]+)\//;
	let gh_handle = '';
	if ( currentHost.endsWith(gi) ) {
		gh_handle = currentHost.replace(gi,'');
	} else if(gr.test(currentURL)) {
		const match = currentURL.match(gr);
		if (match && match[1]) {
			gh_handle = match[1];
		}
	}
	if( gh_handle ) {
		mappings = [[
			`github.com/${gh_handle}/${gh_handle}.github.io/edit/master/`,
			`${gh_handle}.github.io/`
		]];
	}

	mappings.forEach(prefixes => {
		prefixes.forEach((prefix, index) => {
			if (currentURL.startsWith(currentProtocol + prefix)) {
				const nextPrefix = prefixes[index + 1] || prefixes[0];
				const newURL = currentURL.replace(prefix, nextPrefix);
				document.location.href = newURL;
			}
		});
	})
})([
/*
Place hostnames/URL prefixes without protocols in here
like so:
['www.prod.ext/','edit.int/'],
['some.prod/', 'our.dev/UAT/', 'our.dev/INT/', 'et.cetera/whatever'],
*/
])