Refresh your mirrors and databases, and update your system packages first… 
sudo pacman-mirrors -f && sudo pacman -Fy && sudo pacman -Syyu
Then update the rest…
pamac update
Also, see this handy tutorial below…
The golden rule is to always check the Stable Updates thread first — or at the very least, the first two posts of it — and to also always run…
pacdiff -o
… after updating, so that you would know whether there are any .pacnew files.
No, pacman does not have that, but you can inspect the logs with the paclog utility.
Yes, and that is unfortunate. At the risk of once again being misunderstood, Manjaro is not a suitable distribution for people who regard their system as merely a kitchen sink appliance — which is exactly how Microsoft and Apple want you to think of your computer, and how they have thus conditioned their user base to think.
Manjaro is based upon Arch, and even though Manjaro is a lot more user-friendly than Arch, it still is and remains a very technical distribution. This does not mean that you have to be a computer scientist in order to use Manjaro, but it does require a certain commitment and sense of responsibility from its users.
It’s a distribution that requires periodic maintenance and a willingness to learn and get one’s hands dirty, so to speak, both because of its Arch roots and because of the fact that it’s a (curated) rolling-release distribution.
“Rolling release” means that the system is not updated/upgraded monolithically, but rather in small and sometimes not-so-small increments of the versions of different components, but with different incremental steps depending on the exact components. As such, it’ll never be as smooth as a fresh install of a point-release distribution like Ubuntu, Mageia, Mint, et al — and mind you that even said other distributions bring along their fair share of hiccups.
All things considered, Manjaro is a rock-solid distribution if one is willing to learn and pay attention. Occasional gotchas do pop up from time to time — some worse than others — but just as an example, I installed this system in late April 2019, and I have so far never had to reinstall.
I did have to restore a timeshift backup once — due to the Plasma 5.25 fiasco, but that was obviously an upstream problem — but other than that I’ve so far never had any serious problems with Manjaro, and I’m using it as my daily driver.
