Um, I selected a whole measure, to add something, this is what happened
I selected an entire measure to add stacatto to all the notes. There came a section where this happened 
Please don't ask me what I'm arranging BTW, I'm only doing it because I'm bored.
Comments
In order to help, we'd need to attach the specific score you are having trouble with and precise steps to reproduce the problem. Also say what version of MuseScore and what OS. When I try entering something similar in the current release (2.0.3( on Linux, selecting the measure, and applying staccato, it works as expected. So I'm guessing you have some manually adjusted stems or some such causing trouble.
In reply to In order to help, we'd need by Marc Sabatella
I posted this because I was having trouble with the nightly build. Not 2.0.3. I am very aware that 2.0.3 works normally in this area.
Here are the specific steps.
You can see that I have some notes entered in the violin 2 and cello part. Select all of those notes, (Make sure the blue box is around all the notes) and then double click the staccato under articulations and ornaments. Then, observe how it looks like the picture I posted.
Or, you can manually input those notes in a different measure, then you select all and make sure the blue box is around all notes in violin 2 and cello part, then double click the staccato under articulations and ornaments.
This only works under nightly builds, the 3.0.0 one.
In reply to I posted this because I was by Elwin
Confirmed, and not just when applying the staccato to the entire measure, but also when applying it to that first note in bottom staff only, or any of the 9th to 12th 8th in 2nd staff.
Selecting the staccato and using X to flip it give even weirder results, it ends up way too far away from the note and wrongly aligned too
Please report in issue tracker.
In reply to Confirmed, and not just when by Jojo-Schmitz
From the look of it, it seems the staccato marking only considers the default stem direction of the note as if it were a single note and not the consequence of beaming with other notes flipping the stem.
In reply to Confirmed, and not just when by Jojo-Schmitz
Issue What? How do I do that? I did try this on 2.0.3, and it was normal.
In reply to Issue What? How do I do that? by Elwin
Bug reports should normally be filed in the issue tracker - either using the link in the menu at right of this page, or else using Help / Report a Bug. If there is any doubt at all over whether something is a bug or just a misunderstanding, though, it's best to discuss here in the forums first.
Realistically, the current nightly builds for 3.0 are in a state of transition right now (since a very big change to the layout algorithms was made a few weeks ago) and the builds are known to have very many issues. That doesn't mean you shouldn't submit bug reports - quite the contrary! - but it's good to go in to nightlies with realistic expectations. They are not intended for real work, just for testing. The whole *point* of using them is to held find bugs, and I expect you'll have no trouble doing so right now :-)
When filing a bug report, you'll see you can specify which version the bug applies to. Pick 2.0.3 if the bug exists in that version, 3.0-dev if it's only in the nightly build for 3.0.
In reply to Bug reports should normally by Marc Sabatella
So, I reported this under technology preview because this was a nightly build issue. If it was an issue for 2.0.3, then I would post this under Support. So what you're telling me is that if I have a bug report in nightly build, then I should report this under issue tracker. Is that right?
In reply to So, I reported this under by Elwin
Yes. If there is any doubt about whether it is an actual bug, you should post to this forum first, otherwise just submit to the tracker.