Hi Jack, thanks for replying! The error does not happen using "emacs -q" (built-in package: org 9.3). I haven't tried with the git version yet. i will and let you know. Cheers, Sebastian On Sun, Nov 1, 2020 at 9:19 PM Jack Kamm wrote: > Hi Sebastian -- > > > I am having problems with the fontification of python and ipython source > > blocks when the code contains curly brackets "{}" (other course blocks > are > > ok). For instance, the following snippet > > > > #+BEGIN_SRC python :results drawer > > import matplotlib.pyplot as plt > > plt.plot([1,2,3]) > > plt.show() > > a=1 > > print("a={}".format{a}) > > #+END_SRC > > > > does not fontify correctly in either python or ipython source blocks. > > > > As a consequence, when exporting the org file to HTML (C-c C-e h h), it > > fails with the following message: > > > > font-lock-fontify-keywords-region: Invalid function: # > > I'm unable to reproduce this behavior on emacs 27.1 and git > master. Fontification and export work fine with this code block for me. > > Does the error still happen when you use emacs -q ? Or if you use git > master? > > Jack > >