Thank you for your support.
And thank you for reporting issues, it is important it helps me to make Drop Feeds better.
I will take a look at that and see how I can fix that.

Edit:
1. about "click the Drop feeds button twice for the sidebar":
- I can't fix that, because "browser_action" button is not designed (at Firefox level) to open the side bar but a popup window. Then Drop Feeds uses a workaround to open the sidebar, but this implies that when Drop Feeds is not loaded to click twice.
2. about "...with the Tom's Hardware RSS feed. Just shows the same article multiple times.":
It is fixed in 0.7.13

Edit2:
About "click the Drop feeds button twice for the sidebar":
It is fixed in 0.9.4alpha1, available here: https://github.com/dauphine-dev/drop-feeds/releases
It will be available on AMO when 0.9.4 will be ready.