The Linux Mint project has been dealing with a number of bugs in core packages since the release of Linux Mint 19. The new release, which is based on Ubuntu 18.04, has run into regressions in the MESA, GRUB, kernel, and WINE packages. In the project's July monthly newsletter the team addresses some of the concerns and discusses efforts being made to fix these problems. "More recently, a GRUB update triggered an issue in one of our own packages. That issue could only be triggered by a new GRUB update and so it had gone undetected during QA and the beta test. Although it was fixed in a matter of hours in the repositories, it still affects our installation ISO images and it breaks EFI installations when the live session is connected to the Internet. The release notes were updated to ask people to install offline. New 64-bit ISO images for Linux Mint 19 Cinnamon, MATE and Xfce were produced with the fixed package and they passed QA yesterday. These new ISOs will replace the current images in the days to come.
Be careful with Kernel 4.15.0-24. A critical issue causes some computers to boot really slowly, or not to boot at all. Ubuntu is aware of it and working on a fix. We've also received negative feedback from the 4.15 kernel series in Mint 18.x (based on Ubuntu Xenial). Although Ubuntu decided to switch the HWE series towards it, the 4.15 series doesn't appear to support some proprietary drivers yet (nvidia-3.04 and nvidia-340 among them).
We're also aware of regressions in the Bionic base affecting VPN, Samba, WINE (recently fixed). Ubuntu 18.04 is a brand new base and we're sure it will settle, receive bug fixes and get more mature with time."