[danwdoo]

The tweak options are really much simpler now than what I dealt with when I made this change. I think you'll have no problems doing this and trust me it's worth the little effort it takes. Maybe these instructions will help make it easier:

1) Click on the preferences icon in the toolbar. It's the one that looks like a set of little gears. A new window will open with all the vaious preference categories.

2) Click on tweaks icon at the bottom of the page. It looks like an open drawer. The tweaks screen will then open.

3) In the left hand pane are all the varirous options. The top one is called "Control behavior of double clicks...". Depending on your screen size, it may affect how much of the title is visible before the three dots appear. Single click on the entry with the left mouse button. In the top pane of the screen, the following text will then appear:

Behavior of doubleclick on the books list. Choices: open_viewer, do_nothing,
edit_cell, edit_metadata. Selecting edit_metadata has the side effect of
disabling editing a field using a single click.
Default: open_viewer.
Example: doubleclick_on_library_view = 'do_nothing'

In the bottom pane will appear the following:

# Control behavior of double clicks on the book list

doubleclick_on_library_view = 'open_viewer'

4) The only part you need to look at is the bottom pane. The last line should say:

doubleclick_on_library_view = 'open_viewer'

All you have to do is change open_viewer to edit_cell so that the line now looks like:

doubleclick_on_library_view = 'edit_cell'

5) Click the apply button to accept the change and then close the window as well as the preferences window.

I think if you give it a try, you'll find it's really very straightforward. You may need to restart Calibre before this takes effect but I'm not sure on that.