I can toggle visibility of the right palette by clicking this button: 
Is there also a way to toggle visibility of the left palette (Shapes) without using "Fullscreen" button?
Answer
How to hide "Shapes" palette?
Best answer by Sami H
Hello there
Thanks for posting in the Community! Yes this is possible. There should be a button the far upper left corner (to the left of the word "shapes") that looks like a square with a circle in front of it. If you click on that it should hide the shapes panel. I have attached a picture for reference. Hope this helps! 
Hello there
Thanks for posting in the Community! Yes this is possible. There should be a button the far upper left corner (to the left of the word "shapes") that looks like a square with a circle in front of it. If you click on that it should hide the shapes panel. I have attached a picture for reference. Hope this helps!
Easy enough! Thank you.
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