Migrating from 2018.3.x to 2019.1

After upgrading from 2018.3.x to 2019.1 nearly all of my shaders broke, prefabs were removed from my scenes, I was spammed with nearly 200 errors from the Shader Graph (which I didn't have installed) and Text Mesh Pro v2.0.0 (which I did have installed, but says it's 2019.1 verified in the package manager) I tried several different things but none worked. I eventually created a new project and moved my Assets over which solved the Shader Graph issue, but is still causing the same problems with Text Mesh Pro. Additionally, the 2019.1 upgrade guide provides essentially no information. Did I do something wrong? Are these bugs in the release?