编辑“︁Template:Overlay/doc”︁（章节）

===Deficiences===
====Automatic column balancing====
While the template will handle missing set overlay values at the start, that is the first overlay item does not have to be overlay1, the template treats intermediate missing overlays as though they exist for column balancing, and it does not allow for any text wrapped new lines within an overlay item's text.

====Undeterminable legend start and ends====
If legend titles are provided without a corresponding start or end and the template cannot explicitly determine one from an adjacent legend then it will "guess" and unexpected results might be produced, which might not be stable with any template updates.

Legend start and end ranges can be overlapped.  This is either a deficiency or a feature depending on how you look at it.  However, overlapping ranges might result in unexpected behaviour, which might not be stable with any template updates.

====Double quotes in pop up tips for overlays====
Double quotes, '''"''', cannot be placed in overlay tips when ''form = text'' or when ''form = colour'' are used.  To include a double quote use its HTML coding, '''&#34;'''.

Double quotes are always allowed in the overlay, but if the overlay tip for that overlay is not set separately, the tip, which defaults to the same text as the overlay, will probably not display correctly.  The overlay tip for an overlay with double quotes in it should always be set explicitly when ''form = text'' or when ''form = colour'' are used.