The indicator looks for bars without one or two wicks. DRAW_ARROW drawing style.

Two indicator buffers are used - one signals the absence of an upper wick, while the second one informs of the absence of the lower wick. Both drawing styles apply the same label (Symbol code to draw Shadow parameter) colored differently. The label codes can be found here:

• MetaEditor - MQL5 Reference - search for "Wingdings"
• on the website: Wingdings

Label shift is set by the Arrow shift parameter.