The problem is that the right image has been prepended with the domain and its path twice, that because the first time (I am talking of the second match from left to right) the protocol isn’t separated by the comma : from the domain. If you look better you have https//mademoiselle... in place of https://mademoiselle.... It means that the browser considers that address a relative path, in a subfolder of the current path, and prepend the path of the current page to it.
In brief, somewhere you generate that kind of address with the wrong protocol, look at the _config if you have https// in place of https:// or https in place of https:.
Also, somewhere in your post templates look if the URL is hardcoded or refers to the wrong variable.
That depends on how URLs are generated inside the template, I remember a change in that sense when Jekyll switched to the 4th version, probably the template hasn’t been correctly updated?
I’ve tried to use the last version, but seems I’m obliged to use 3.X for “jekyll-paginate” to works… but I really don’t know why and I don’t investigate more on that point.
I start to have the sensation that the theme I used is in fact a little bit “old” no ?
One question more, cause I’m a complete newby on Jekyll. I understand how important to use the last version of a CMS like WordPress for example (for security purpose). Using the last version of Jekyll is “important” if your website runs without problem online ?
You’re welcome! If you want to learn more about it, I recommend starting a dummy website to use only for tests and development, first the site and then a small theme, only putting the hands-on you will learn more.
Until you deploy uploading manually the _site content don’t have to worry about the plugins you can include in your project.