Ok, i got a mistake to use indirect buffer in this way. The text properties of base buffer are shared with indirect buffers. Due to svg in emacs is not fully support, i have implemented this by using =impatient-mode= with web-browser, when the svg file modified the preview will be changed at the same time. Michael Heerdegen writes: > PENG Kevin writes: > > [+] >> The text of the indirect buffer is always identical to the text of its >> base buffer; changes made by editing either one are visible >> immediately in the other. “Text” here includes both the characters and >> their text properties. > > `image-mode' uses text properties to display the image! Most major > modes use text properties to font-lock the buffer and change the way how > its contents are displayed. > > Use cases of indirect buffers are limited, maybe we need to warn more > explicitly that their usefulness is very restricted. IIRC, having > indirect and base buffer using different major modes is something that > was never supported. > > From the past discussions about the matter I also recall that the > limitations are lying in the concept and we can't do much here without a > reimplementation of the idea. > > So I would suggest to rather think about how to get what you want > without using indirect buffers. > > > Michael.