This was created in response to a bug reported for Markdown Here: in Blogger, after saving a draft, it was no longer possible to unrender from HTML to Markdown.

I discovered that Blogger is mangling the title attribute name that Markdown Here uses to hold the original Markdown, thereby preventing MDH from find it. Furthermore, Blogger was mangling the inline style attribute name (for some elements -- only deeper elements?). However, when publishing the blog post, the styles would be restored. In addition to hurting MDH's functionality and interfering with its sweet styling being shown properly, this also affects the styling of rich content which has been pasted from other web pages.

So, not only does this weird mangling behaviour totally break Markdown Here, it breaks the what-you-see-is-what-you-get (wysiwyg) user experience that everyone expects.

Get it from the Chrome Store.

If you would like to be able to use a hotkey to trigger it, you can use the Chrome's built-in hotkey assignment feature by pasting this address into Chrome:
chrome://extensions/configureCommands

Just place focus into the Blogger edit box and click the toolbar button. All inline styles will be immediately restored. And Markdown Here will work again.

Note: The address of the page you're on while editing your blog post must begin with https://www.blogger.com/. If this is too restrictive, please create an issue.

In Firefox (and probably Internet Explorer and Safari) you can create a bookmark with the "Address" or "Locaton" or "URL" set to the following JavaScript. It will function basically the same as the extension.

javascript:((function(){var doc=document;while(doc.activeElement.contentDocument)doc=doc.activeElement.contentDocument;var elems=doc.activeElement.querySelectorAll('[data-blogger-escaped-style]');for(var i=0;i<elems.length;i++){elems[i].style.cssText=elems[i].dataset.bloggerEscapedStyle;}elems=doc.activeElement.querySelectorAll('[data-blogger-escaped-title]');for(var i=0;i<elems.length;i++){elems[i].title=elems[i].dataset.bloggerEscapedTitle;}})())

If anyone wants to provide a better one, that isn't such a copyright violation, that would be great.