JSONovich - Firefox Add-on - JSONovich is a Firefox extension that pretty-prints JSON content of various types directly in a browser tab. It uses the browser's native JSON parser and a custom-built formatter to produce its output.
Normally, Firefox would prompt to download JSON sent with the correct application/json mime-type
MuLTiFlow - A WYSIWYG rich text editor that uses the HTML+MathML+SVG support in Mozilla-XUL. UTN28 support is also available for Math. SVG support is also available but to create SVG markup one might require a separate application such as Inkscape or SVG-Edit (a Firefox addon)
Cloud Printer adds remote printing support to Firefox. This allows you to print web pages from the browser to your printers using the new Google Cloud Print service. The service is still in Beta, but seems to work pretty well. Before using this add-on, you will need to install and configure Google Cloud Print on your PC
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