The Mertens function M(x) is defined as follows.
$$\quad M(x)=\sum\limits_{n\le x}\mu(n)$$
The following table lists the consecutive zeros of $M(x)$ of length $l\ge 2$ for $0<x\le 1000$.
$$\begin{array}{cccc} 39 & 40 & \text{} & \text{} \\ 149 & 150 & \text{} & \text{} \\ 159 & 160 & \text{} & \text{} \\ 163 & 164 & \text{} & \text{} \\ 231 & 232 & \text{} & \text{} \\ 235 & 236 & \text{} & \text{} \\ 331 & 332 & 333 & \text{} \\ 355 & 356 & \text{} & \text{} \\ 362 & 363 & 364 & \text{} \\ 403 & 404 & 405 & \text{} \\ 407 & 408 & \text{} & \text{} \\ 413 & 414 & \text{} & \text{} \\ 419 & 420 & \text{} & \text{} \\ 422 & 423 & 424 & 425 \\ 427 & 428 & \text{} & \text{} \\ 607 & 608 & \text{} & \text{} \\ 635 & 636 & 637 & \text{} \\ 795 & 796 & \text{} & \text{} \\ 811 & 812 & \text{} & \text{} \\ 823 & 824 & 825 & \text{} \\ 849 & 850 & \text{} & \text{} \\ 883 & 884 & \text{} & \text{} \\ 895 & 896 & \text{} & \text{} \\ 903 & 904 & \text{} & \text{} \\ 915 & 916 & \text{} & \text{} \\ 919 & 920 & \text{} & \text{} \\ \end{array}$$
The following table lists the consecutive zeros of $M(x)$ of length $l\ge 5$ for $0<x\le 10,000,000$.
$$\begin{array}{cccccc} 45371 & 45372 & 45373 & 45374 & 45375 & 45376 \\ 79934 & 79935 & 79936 & 79937 & 79938 & \text{} \\ 246473 & 246474 & 246475 & 246476 & 246477 & \text{} \\ 265471 & 265472 & 265473 & 265474 & 265475 & 265476 \\ 393046 & 393047 & 393048 & 393049 & 393050 & \text{} \\ 973823 & 973824 & 973825 & 973826 & 973827 & 973828 \\ 1246849 & 1246850 & 1246851 & 1246852 & 1246853 & 1246854 \\ 2329323 & 2329324 & 2329325 & 2329326 & 2329327 & 2329328 \\ 2914223 & 2914224 & 2914225 & 2914226 & 2914227 & 2914228 \\ 2944673 & 2944674 & 2944675 & 2944676 & 2944677 & \text{} \\ 3946291 & 3946292 & 3946293 & 3946294 & 3946295 & 3946296 \\ 3946823 & 3946824 & 3946825 & 3946826 & 3946827 & 3946828 \\ 3954247 & 3954248 & 3954249 & 3954250 & 3954251 & 3954252 \\ 7810746 & 7810747 & 7810748 & 7810749 & 7810750 & \text{} \\ 9591602 & 9591603 & 9591604 & 9591605 & 9591606 & \text{} \\ \end{array}$$
Question (1): What is known about the number of consecutive zeros of the Mertens function? For example, is it true there are an infinite number of consecutive zeros of M(x) of length $l$ for any positive integer $l$?
Question (2): Is there a relationship between conjectures on the number of consecutive zeros of the Mertens function and the Riemann hypothesis?