--level used:7When a leftJoin is used with the query builder it will be seen as returning Illuminate\Support\Collection instead of Illuminate\Database\Eloquent\Collection.
If you leave out the leftJoin it actually detects the correct type.
$user->clients()->leftJoin('keywords', 'keywords.keyword_group_id', '=', 'keyword_groups.id')->get();
Can you test this with the latest changes in master branch?
Sorry I no longer have access to the affected source.
Thank you for your answer.
OK. So I'm closing this.
Most helpful comment
OK. So I'm closing this.