Add a arrow key to toggle Sketch Files Section

[rahulrana701]

Increasing Access

For mobile users , by applying the arrow key in sketch files section near add sign , will make much more clear to the users like this button is used to toggle this particular section , and user would be able to see the code files fully.

Feature enhancement details

I will add this particular icon which will toggle this section , @lindapaiste so I would like to work on this issue , please assign it to me

[rahulrana701]

@lindapaiste done

[katiejliu]

This issue seems similarly related to this issue #2888

In which the discussion is of improving the overall UI of this area on mobile and web @raclim

[raclim]

Thanks for pointing this out @katiejliu! I'm going to close this as a duplicate.