If you directly select the "Mail" item on the "Settings" panel the mail "Options" panel will open on the left side of the browser.
On the "Options" side panel dive into "Region and time zone" settings under the "General" group. On this page you'll see an extra checkbox which reads as "Rename default folders so their names match the specified language". I ...
When you click the checkbox to select all the emails the email content window displays a menu which includes the buttons of options for the selected emails which has a header counting the number of selected emails. You can find the selection url for all the emails just below this header which reads as "Select everything in your Inbox folder".
As of 19-07-2017, this is currently not possible.
Given that the URLs of the images follow this pattern:
IMAGE_LINK is unique to each image so recursive retrieval is nearly impossible. I've even tried using wget using the command:
wget --spider -r --no-parent --no-check-certificate https://eus-...
Here is a quote directly from the Microsoft Community Forum:
"please be informed that this is not possible since it is by design that Skype is already integrated in the Web Messenger."
I don't know if it will resolve the issue, but you can try unlinking your Skype and Microsoft accounts.