Alain, one way to work around the size limitation of images uploaded directly to the WW&F forum is to use a 3rd party 'photo host'. There are a number of photo hosts available, some with fees and some free of charge.
One that is free of charge, and I use and like is PostImages.org.
https://postimages.org/PostImages internally takes care of managing the image size, so there are no restrictions on sizes you can upload. Creating an account is
not required, but if you do create an account then its easy to manage the images that you have previously uploaded.
Once you upload a photo to that site, it presents you with a link that you can copy. Then come to the WW&F site and paste that link into your message.
If you have any issues using Postimage with the WW&F site you can send me a PM / Private Message and I'm sure I can resolve them.