Mitigation Type allows users to select how FVGs should be mitigated, either by wick or by completely closing through the area.
The displacement option helps to filter out smaller FVGs by looking for areas where price ran rather quickly (causing displacement). This is done by comparing the candle that made the FVG to a fractional ATR value, so that one may fine-tune how much “larger” the candle range needs to be, relative to recent price action.
The timeframe alignment option allows users to select how many timeframes must be converging in order to draw FVGs. For instance, with all timeframes selected, a timeframe alignment value of 2 would require that there be overlapping FVGs on 2 or more timeframes. A value of 3 would require that there be overlapping FVGs on all 3 timeframes in order for them to be drawn.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.