I've discovered a bit of a bug that is frustrating me. I've been able to troubleshoot and recreate a (not) working example.
With the stock chart, the zoomType: 'x' feature behaves erratically when the xAxis ordinal is set to true, and I include a 'flags' series. This behavior gets even worse the more flags series I include in the chart. When I try to zoom in (in this example, try zooming more than once), the zoom will eventually only go to the last point in the series even though I've selected a range of 1 month or so.
To reproduce the issue, use this Fiddle: https://jsfiddle.net/59nsbe0a/
Zoom a few time by dragging a range on the x axis - select a range of about a week or two, and eventually it will only display one OHLC bar. If I click the "6m" zoom button, then try to select ANY range within 6 months, the problem persists and it only shows 1 bar.
If I remove the flag series completely, there is no issue: https://jsfiddle.net/59nsbe0a/2/
If I leave the flag series, and set the xAxis ordinal to false, there is no issue except for the gaps from weekends/holidays: https://jsfiddle.net/59nsbe0a/3/
If I add another 'flags' series, the zooming issue gets even worse: https://jsfiddle.net/59nsbe0a/4/
So somewhere there is an issue between the xAxis ordinal and the 'flags' series type causing the click-and-drag or pinch (on mobile) zoom to fail.
Any thoughts as to how I can fix this? Thanks in advance.