The standard advice people get when they complain about some bug or difficulty with Emacs is to restart it with -q or -Q to see if the problem persists. The problem with that advice is that the difficulty may be with a package. In that case you want to load at least the offending package and its configuration. That used to involve moving or renaming your init.el so that you could install the minimal init.el that produced the problem. As of Emacs 29 that got easier with the introduction of the --init-directory parameter that tells Emacs to load it’s configuration from a different directory.
Protesilaos Stavrou (Prot) has a nice post that explains how to use this feature when you experience a problem and want to file a bug report. The main problem, of course, is what to put in your new init.el. Prot recommends using use-package with :ensure t (and whatever configuration you’re using) to load the package.
Sometimes you might have to build the package from source rather than simply loading it from one of the ELPA repositories. Prot discusses how to do this using package-vc-install to grab the source directly from its git repository. He has some sample code showing how to do this.
Finally, he has some general recommendations that you can use to make the developer’s life a bit easier. On the other hand, if you are the package developer, the --init-directory trick can save a lot of time in locating bugs. In either case, take a look at Prot’s post. There’s a lot of good information in it.