Short description: Invoking C-c ' (org-edit-special) on an org src block containing an ascii diagram causes table recognition and font lock glitch if the diagram has a rectangle in it.
Long description: Invoke C-c ' on any of the following three src blocks #+BEGIN_SRC artist +---------+ | | | box1 | | | +---------+ #+END_SRC #+BEGIN_EXAMPLE +---------+ | | | box2 | | | +---------+ #+END_EXAMPLE #+BEGIN_ASCII +---------+ | | | box3 | | | +---------+ #+END_ASCII and org src mode will trigger table recognition (message "Recognizing tables...done" in echo area) and leave some font lock glitch such as blue background inside the rectangle. Another glitch is that if the user uses variable-pitch for text outside source blocks and fixed-pitch for text inside them, the org-src-mode buffer will be in variable-pitch font after table recognition is triggered. This bug sometimes disappear on second invoke of org-edit-special of the same block. Workarounds for now: 1. Prefixing the diagram (with dots in this case): #+BEGIN_EXAMPLE . +---------+ . | | . | box | . | | . +---------+ #+END_EXAMPLE 2. Using a colon block which does not have the benefit of being foldable: : +---------+ : | | : | box | : | | : +---------+ 3. Not using + in rectangle corners: #+BEGIN_EXAMPLE --------- | | | box | | | --------- #+END_EXAMPLE