matrix - Multiplying SparseArray by negative number Crashes Kernel

Bug introduced in 9.0 and persisting through 11.0

Can anyone reproduce the following bug, or figure out a work-around. The following crashes the kernel on both Mathematica 10 and 11, on my macs, running OSX 10.10 and 10.11:

Cl[len_Integer] := SparseArray[{
  Band[{1, 1}] -> Table[-2., {len}],
  Band[{1, 2}] -> Table[1. + 1./(2 j - 1.), {j, 1., len - 1}],

  Band[{2, 1}] -> Table[1. - 1./(2 j + 1.), {j, 1., len - 1}]}, 
  {len, len}]

s = Cl[30]

t = -2. s

The last line (simply multiplying the matrix by a negative number) causes the crash. I have tried changing the matrix -- and some changes help, other do not. Multiplying by positive numbers is fine.

Answer

This is a bug. From @ilian's comment:

Workaround: turn off the Suggestions bar.

Comments

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