Question: Is there regex to catch every character except one?
For instance every characters in curly brackets until open curly bracket is found, then don't match that. For instance catch:

```
{lorem ipsuem}

```

but not:

```
{lorem ipsum {lorem}

```

because there is another `{` within
I've tried different solution like:

```
\{[^\}].+?(?=)\} or \s\{[^\}].+?\s(?!\{)\}

```

Answer: 
I had a similar problem this week, what worked for me was to uninstall the entity framework tools and reinstall them again. 

1. uninstall: `dotnet tool uninstall --global dotnet-ef`
2. install again: `dotnet tool install --global dotnet-ef --version 3.0.0-*`

For me the `--version` did the trick as otherwise I got a wired error.
Just a guess, but i think your references of EF in your project is still old. Can you try that removing reference of EF from your project and add it again (which will get you updated version of EF)