## Todo list
* Browser: add cookie support
* Browser: support pop window, such as emacs-china.org
* Browser: add progressbar
* Browser: add proxy support
* Browser: implement js plugin like vimium
* Browser: study more code from https://github.com/LavaPower/Browthon-Old/blob/c25d5721b40e95131a3c521566a18467f13ecbf0/files/Browthon_elements.py
* ImageViewer: add zoom support
* Pdfviewer: hover mouse to detect url postion, ctrl + button can open url under mouse.
* Pdfviewer: fix page still in scrolling even user release key.
* PdfViewer: use mupdf/page.searchFor implement search text in pdf.
* PdfViewer: split window first, then scroll event cause view blank
* Terminal: https://github.com/hrngultekin/pyqtermwidget5 looks good enough
* CHMViewer: develop a chm viewer in emacs.