Allow filtering by tag

[ianhinder]

Goal

• As a user
• I want to be able to view only those tasks in Kanban view with a specific tag
• so that I can focus on those tasks only

Suggested approach
In order to achieve this goal I suggest to replicate the things3 UI where tags to filter by can be chosen at the top of the page

Additional context

• screen shot

My own use case is that I use the same database for work and personal items, with Work and Personal being Areas in Things3. I have Work and Personal tags on the Areas, allowing me (in Things3) to focus on either of these in any of the task lists. Without this, my Kanban view is full of both work and personal tasks.