When custom drag handle position bottom left, drag effect do not work very well

[yanhaijing]

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When custom drag handle position bottom left, drag effect do not work very well, The gif animation is as followswhen custom drag handle position bottom left, drag effect do not work very well, The gif animation is as follows

Simple modification of the official website example, can be debug

from https://github.com/valor-software/ng2-dragula/issues/1024