As it is not possible to retrieve the logo files directly from the computer, you must first upload them.

 Start by going to :

Enter the Saas user and password again.

Click on upload a new file:

Click on upload a file :

Get the file :

Click on Done.

It is ready for ujse.

Go normally to the format editor, click on the image insertion icon.

It will prompt :

Answer Yes.

Select the desired file and proceed as usual.

 When it is done, do not forget to delete the file in the loading screen if it is not needed elsewhere:

(Screen layout may differ a little bit but the actions are the same)