The sidebar takes up a considerable amount of space and it is not necessary when user works on a note or todo, not to mention if user uses split layout with markdown preview. Some button to quickly hide/show sidebar could be useful. It would hive user more space and let her focus on writing.
I fully agree! I started using joplin not only for notes and todos but rather as some kind of a portable „mini-wiki“ which often ends up in longer notes incl. images. Toggling or hiding the sidebar would be a desirable feature for distraction-free writing longer entries or articles. +1
...and a shortcut for that would be extremely handy!
Hi there,
This is something that I'd be interested in as well, and will see if I can invest some time in doing myself.

Please find the screenshot above.
We can add a Toggle Sidebar button there, and under the View menu at the top. This will completely collapse the sidebar and the other two windows will grow to take its shape.
A shortcut key will be provided that allows you to collapse and expand the sidebar.
Eventually (maybe as part of a separate issue) we can look into a button that collapses the sidebar to semi collapsed state from where notebooks and tags are still view-able.
@laurent22 - Thoughts?
@Abijeet, I think that sounds good as you described it. If you need any help implementing it, feel free to let me know. Please make sure you get the latest version from master though as the toolbar has changed a bit (in particular the search bar has been moved to it).
@laurent22 - Implemented this here - https://github.com/laurent22/joplin/pull/424
Here's a screenshot,

Let me know if you'd like me to change anything.
Most helpful comment
@Abijeet, I think that sounds good as you described it. If you need any help implementing it, feel free to let me know. Please make sure you get the latest version from master though as the toolbar has changed a bit (in particular the search bar has been moved to it).