golang.org/x/net/html has Improper Restriction of Operations within the Bounds of a Memory Buffer

The html package (aka x/net/html) through 2018-09-25 in Go mishandles <svg><template><desc><t><svg></template>, leading to a panic: runtime error (index out of range) in (*nodeStack).pop in node.go, called from (*parser).clearActiveFormattingElements, during an html.Parse call.