Using version 3.x

People seem to think that MuseScore 3 is nothing more than an update to MuseScore 2. This is not the case, and I've put together a little document that might give you a little insight into what MuseScore 3 offers.

Using MuseScore 3

This document is intended to be a concise guide to using version 3 of MuseScore. It is directed toward users of version 2, but would mostly be useful for anyone using MuseScore for the first time. This is also not comprehensive or designed to replace the handbook. For detailed instructions, you can search the handbook for terms found in this document.

Version 2

If you used version 2, then keep it installed. If you don't take any action, it will remain on your computer. Version 2 is under a folder call MuseScore 2, while version 3 is under a folder called MuseScore 3. When you install version 3, all MuseScore files are automatically associated with version 3. This means that double clicking a .mscz file will open it in version 3. You will get a message that you have opened a version 2 score asking if you want to reset default positions on the score. If you don't save the score, you can open it again and change your answer. I recommend using version 2 for version 2 scores and using version 3 for new scores. There is no reason to convert a score from version 2 you are happy with.
If you do decide to convert a version 2 file to version 3, save all version 3 scores in a location reserved for version 3 scores so you don't get the two mixed up. Version 3 files cannot be directly opened by version 2.

Adjusting to version 3

Version 3 is not version 2. You need to learn some new things about how it works. First of all, in version 2 you were able to drag things around the screen at will. While this was often not the best method to position items, it usually gave the results you wanted. In version 3, if you try to drag something around the screen, it will probably fight you. You cannot drag things below the staff, but there is a better way in version 3. Use the inspector (press F8 if you don't see it). Most items that are not notes have a placement field in the inspector. If you want to move it from above to below the staff you can change this field from above to below. Often you can simply select the item and press X to move it, but there are some exceptions. This is a good point to look in the handbook if you're afraid to press the X and find out if your item will move.
Version 3 has an auto placement algorithm that positions items in a manner the programmers thought would be the most often used. Many of the decisions were based upon the standards set out in Elaine Goulds Behind the bars. If you move a text item with auto placement still turned on, other text itmes that are avoiding it, will continue to avoid it in the same direction. If you want a Tempo below a Staff text, you will have to turn off auto placement on one of them. If you don't do this, the Tempo will remain above the Staff text no matter how far you move them, or they will refuse to move because you can't move either of them onto or below the staff while auto placement is turned on.

Automatic Placement

Automatic placement (called auto placement in this document) is a blessing. Version 3 doesn't display scores exactly as version 2 does, but that's another story. It's also the reason I suggest that you use version 2 for version 2 scores.
Auto placement makes it so you no longer need to move every lyric because they crash with the B-flat below the staff for example. It also make it so hairpins no longer overlap dynamics and very few things need adjustment unless you just don't like the way it looks. This is my favorite feature.
Auto placement also adjusts the space between staves so spacers are necessary less often. You can put a set distance between staves if you want, but most auto adjustments are minor so spacing differences are minimal.

Dynamic measures

In version 3 it's much easier to adjust the duration of a measure. If you need to make a pickup measure, select the rests you don't want and press ctrl+del and the measure will shorten by the duration of those rests. An added bonus is the blue minus sign ( - ) that will appear above the end of the measure. This tells you the measure is shorter than the time signature says it should be.
You can also add beats to the measure. The easiest way is to press ctrl+shift while pressing the letter for the note. A note of the selected duration will be inserted and a blue plus sign ( + ) will tell you the measure is longer than the time signature.
You still have the option to check "Display note values across measur boundaries" if you're entering a chant. Now it's easier to shorten the measure if you're ready to start a new one.

The Inspector

In version 2, many items had properties that could be accessed by right clicking them and selecting xxx Properties. There are now few things with meaningful properties. These are pretting much limited to Staves, measures, staff text (for changing instrument sound or swing) and system text (for changing swing settings). Most properties are not located in the inspector, like Fretboard diagrams, lines and bends. When in doubt, click the item and see if the proerties you need to change are in the inspector. If they're not, then there will be Properties you can access through right clicking the item.
The Inspector is now a very powerful tool. Use it more than your mouse and you will be much happier with the results. As I previously said, most properties are now in the inspector, so you can change the text on a line in the inspector. In fact, if you want to change a bunch of "cresc." lines to say "poco cresc." you can select several of them and change them all at once. Search for Selection modes for more info on selecting several itmes at once. In version 2, I often wished I could do this since it's common for several instruments to have the same dynamics instructions.

Menus

Take some time to familiarize yourself with the new menus. There are a couple of new tools and several of the menus have changed. There's even an option to automatically delete the empty measures at the end of a score when you're done.
Things in the works
In the near future some things will be improved. Plugins will be continue to be worked on so you can use the plugins you loved in version 2. Playback will continue to be improved. MDL is not yet adapted to version 3, but that's is being worked on. What is even more exciting is the improved playback that's being worked on. Version 3.1 is scheduled to have dynamic changes on a single note. That's right you'll be able to have a whole note crescendo, which as every MuseScore user knows is impossible. The single note crescendo capability will come with a new sound font as well.