Closes #3998

* \x1a-\x1f were missing though it looks like the intention was to cover all below \x20 (space)
* added \x7f which is usually considered non-printable
* removed \t which was already covered in \x00-\x19 as \x09

Issue #3979

See https://discuss.codemirror.net/t/drag-drop-modifiers/721

Closes #3958

Issue #3956

5.13.4 was a trivial release restoring a LICENSE file.

Closes #3905

Issue #3884

Issue #3884

Closes #3899

Closes #3884

Closes #3846.

Issue #3852

Closes #3846

Closes #3840

Closes #3834

Issue #3821

It doesn't work inside of a transformed container, even for zero
transforms (which some components seem to love putting on root
elements, for whichever reason)

Closes #3238

To avoid messing up the position of the gutter when an offset
bigger than the max offset is given.

Closes #3781
Closes #3788

Closes #3753

See https://discuss.codemirror.net/t/inserting-a-boomark-immediately-before-a-textmarker/590/1

Issue #3736