conjunctions - 'High quality' or 'high-quality'? - English

For the longest time, I have seen and written 'high quality' as such. However, Grammarly just dropped this bombshell on me; Is that correct? My copy of Grammarly is set to British English as that is

Types of Conjunctions in English, What is a Conjunction?

Conjunctions List: Top 100 Popular Conjunctions in Sentences

FREE Types of Conjunctions Poster by PlanBee

List of Conjunctions: Words, Rules, Uses in English Grammar: Words

Exploring Conjunctions: Types, Examples, and Their Meaning in English

The Common Types of English Conjunctions (with Examples)

List of Conjunctions: Words, Rules, Uses in English Grammar: Words

Speeches of english grammar

Subordinating Conjunctions: Definition, Examples, & Exercises

Correlative Conjunctions - Meaning, Example, and Practice Exercise

English Grammar on X: What are conjunctions? #conjunctions