Allow to open markdown files, graph and canvas in new tab as the default behavior.

Changes:

• Fix misbehaviors happening when only one file is open.
• Fix issue of graph views not executing properly.
• Fix issue preventing to write file name right away when creating a new file.

New features:

• Open images in new tab by default.
• Delay option: A delay was necessary to allow a better execution of the code. How much delay is applied is adjustable through an option slider.