[Doxygen-develop] Problem with a filter since Doxygen v1.8.8

[Timo M. <tim...@gm...>]

Hi,

A filter for Google Protocol buffers files I've written (
https://sourceforge.net/p/proto2cpp/) does not work from Doxygen v1.8.8
onward and so far I haven't been able to make it work. It does work with
v1.8.7 and several older versions (oldest I've tested is 1.8.1.1).
Has anyone else encountered such problems with custom Doxygen filters?
Any clues what could be the root cause and how to fix it?

Thanks in advance,
TimoM