somehow my post was not published. Here it is again.
This is an example method of uploading screenshots/pictures to the forum:
1. Upload the pic to a website for pictures like https://imgbb.com/
Click over the picture once it is uploaded and click over the Embed codes:
2. Copy the HTML code starting with the https until .png or .jpg
3. After that go on the Forum and on the post where you want to place the image click on “img” on the top, and paste it there:
4. Than you will see the description filed if you want to place some description, if not leave it empty and click OK.
since you left empty the description you can delete alt=”” part
Anyway Marin is working on new design for the website, and I will ask him to make it easier for the users to upload pictures.
Hope that helps.