Add small Gtk.STOCK_COPY button near 'Password:' fields

[asashnov]

Increase usability: add a small button to copy a password.

Now:

• right click on 'Password:' field value (******)
• move mouse a bit down (but not too far);
• left-click 'Copy password'

With this change:

• left-click on 'copy' button on the right from 'Password:' (after ***** )

Testing strategy

For any entry for your database, try using this new button instead of right-clicking on password, 'Copy password' from the menu. The new button should work the same, but much handy.

Type of change

• ✅ New feature (change that adds functionality)

[asashnov]

Actually, I just realized (after about 10 years of using this app) that it has 'Activate' action on double-click- copy password and open URL of a website.

But I always used clicking on URL field, and manually copying the password.

So, maybe instead (or with) adding this button we should show for the first time URL value is clicked: Did you know you may double-click the enlty in list, so this URL will be opened, and the password copied to clipboard?

Or, alternatively, it may be a tooltip in list for an item under mouse pointer: You can double-click the item to activate. Password will be copied to clipboard and the URL is opened.
(this tooltip should be shown if the entry is a website, and double-click action is 'Activate').

[asashnov]

But my further user experience with the program shows that this 'Copy Password' button is still useful. We can add 'See password' button also to show password 'in place' instead of ******
It can be useful when needed to enter the password into my phone.

[mikelolasagasti]

Thanks for the PR @asashnov !

We can add 'See password' button also to show password 'in place' instead of ******

That would be ctrl+p, that is what I use, but it can be interesting to have that button next to the password.

Would you be interested in extending PR to add that button?