When multiple tasks are selected, drag and drop only affect one task. Is this the expected behaviour?
Yes, that's currently how it works. If you wish to drop them into a different project, please click on the "Move to project" option at the top and all selected tasks will be moved at once.
The behaviour one expects from other programs is that multiple selected objects will respond together to drag and drop.
so Would you consider changing this? Or do you want to keep the current behaviour forever?
We rarely agree to keep something forever except for one thing - a goal to make an easy-to-use app that makes you more productive :-)
That said, we'll surely keep improving the UI and the way it works and as always, you're welcome to add any suggestions to our Votebox which content is always read by all our developers: https://todoist.com/Vote/
Good to know that the developers read the vote section. :)
I have added the request in the votebox: https://todoist.com/Vote/show/8471/