Just my experience, following situations I encounter often playing Blackjack:
- Suppose you have 12 against dealer's 8 and you hit a 6 ending at 18, the dealer draws an Ace, the dealer always seems to get this Ace at the right moment;
- After long grinding play, one makes a big (frustration) bet by clicking the coins fast, often resulting in a blackjack for the player;
- Dealer and player get more blackjack's than at Brick-and-mortar casinos (often in succession, 3 at a row isn't an exception);
- Same for dealer's first card being a 10;
- Same for player busting with a ten card;
Probably this is because of the use of a pseudo RNG which is accepted practice in online casinos to generate outcomes and no problem for third party testers.
Google 'pseudo RNG casino' and you see what I mean.