Docker: correct way to increase upload_max_filesize

[koffienl]

I'm a bit confused on how to properly increasing the php values for max file size. Currently my admin page says: PHP: upload_max_filesize = 25M; post_max_size = 25M

I have increased the docker ENV UPLOAD_MAX_SIZE from 25M to 50M but that doesn't seem to have effect. Thinking this might be een ENV from the previous docker, I created a extra file increase-upload-size.ini outside the docker. Mounted the file as /usr/local/etc/php/conf.d/increase-upload-size.ini inside the docker. The contents of the file:

upload_max_filesize = 2000M post_max_size = 2000M;

Again, no effect. There is no documentation on the docker github (https://hub.docker.com/r/djmaze/snappymail) so I'm not sure where else to look to properly increase the upload size. Can anyone point into the right direction?