CKEditor editing. A custom collaborative solution can be build by using the CKEditor 5 Framework components and real-time collaborative editing can be enabled by connecting to the CKEditor Cloud Services. A ready to use, drop-in component based on CKEditor 5 (Letters) offers a complete solution for real-time collaborative writing. CKEditor 4 is fully compatible with most internet browsers, including latest stable releases from Google Chrome, Firefox, Safari, Microsoft Edge, Opera and Internet Explorer 10 and 11. In mobile environments, it has close to full support in Safari (iOS6 +) and Chrome(Android) CKEditor 5 is also compatible with Google Chrome, Firefox, Safari,
Quirks mode Web Consortium, which maintains the XHTML specification, suggests that authors of XHTML documents could consider omitting the XML declaration. Henri Sivonen compiled a list of various document types and how they are treated in the most common browsers, showing whether pages are rendered in Quirks, Standards, or Almost standards mode. The criterion used for "Almost standards mode" is non-standard table cell height rendering. This table applies to content served with the Content-Type text/html. Content served with the Content-Type application/xhtml+xml is rendered in Standards mode in Chrome, Firefox, Internet Explorer 9, Safari, and Opera. Internet Explorer 6, 7, and 8 do