Thanks for the responses. I think jrl767 in the post preceding yours adverted to the existence of a resizing tool, but that may not be the solution, as it depends on posters doing the right thing, and they may not even realise that there is a need to do so, depending on the device through which they are reading the threads. My impression is that large pictures are most problematic when reading the forum on a desktop computer, and, in my case, the first time I posted a picture, I was myself astonished by how large it turned out.

What would be more useful would be the possibility of having a picture resized on the fly depending on the reader’s preference (and not the poster’s), or even simply to set a fixed maximum or standard size, as online editions of newspapers do, perhaps with the possibility of clicking on the picture to view it at full resolution if so desired. It might also be beneficial to automatically remove images when posts are quoted, as there have been very few threads I have seen where it is necessary to quote an image, in which case a link to the image can instead be supplied.