Defaults to LaTeX Beamer grammar absent a `documentclass` command

[yotamDvir]

Prerequisites

• Put an X in this box if you have done the following:
  • Ensured the issue has not already been raised (searched for "Beamer" and "grammar", found no relevant results)
  • Ensured the issue is caused by this package (find it hard to believe something else causes this, don't know how to ensure this otherwise)

Description

Thinks grammar of some of my .tex files should be LaTeX Beamer for no reason. By the way, I woudn't mind just this, but I do mind that it disables my spell-checker.

Steps to reproduce & Minimum working example

1. Open a new file, keep it empty.
2. Save it with the extension .tex.

Expected behaviour

Default to LaTeX grammar. Only assume another grammar if there is some specific indicator.

Actual behaviour

Defaults to LaTeX Beamer grammar.

Additional information

I find that this doesn't happen when there is a documentclass command in the file. But I don't have that in files that are meant to be included using the input command.