[Bug] Potential memory exhaustion when a high number of classes exist at multiple levels in the DOM

[Dogfalo]

This can lead to a situation where the code is trying to generate a high number of combinations.
In my case it was generating over 300 million combinations at which point it used up over 32 GB ram.

This all happens before the config.threshold check so modifying that option does not prevent this scenario.

finder/finder.ts

Lines 150 to 152 in 77d3315

	const paths = sort(combinations(stack))
	if (paths.length > config.threshold) {
	return fallback ? fallback() : null

#84 This PR fixes this.

[antonmedv]

Yeap. We should add threshold to combinations.

[Dogfalo]

@antonmedv What do you think about the proposed PR?