This used for correctly configuring notes used as export templates. Historically those were, and most often still are used for exporting HTML but can be used for formatting any export template. Here, normal writing affordances like changing straight quotes to typographic quotes are harmful so are disabled.
In older versions, this prototype was called HTML Template: existing files are unaffected. The change is in name only and not function.
Although this prototype has the $IsTemplate flag set, app dialogs (correctly) do not list it as an available template.
This prototype's non-default customisations other than $IsPrototype, $Name, and intrinsic map features (height, width, etc.) are listed below.
$Color: "lighter black".
$HTMLFirstParagraphEnd: "" (empty string).
$HTMLFirstParagraphStart: "" (empty string).
$HTMLIndentedParagraphEnd: "" (empty string).
$HTMLIndentedParagraphStart: "" (empty string).
$HTMLParagraphEnd: "" (empty string).
$HTMLParagraphStart: "" (empty string).
$Tabs: "0.375;0.375;0.375;0.375;0.375;0.375;0.375;0.375;0.375;0.375;0.375;0.375;" (see note).
$Text: "<!-- Tinderbox: Prototype: HTML -->" (pus two trailing line breaks)
$TextFont: "Andale Mono".
$Ziplinks: false (un-ticked).
The aim of the default $Text is to help indicate, when exporting pages composed from several notes, from which note content has been drawn. The prototype's default $Text is only inherited _once_ from the prototype. so, if deleted in the inheriting note, it is not re-applied. If the default text is not of help to a user, it can also be deleted at source, i.e. in the prototype itself.
Note: newly added HTML prototype notes now offer a dozen tab stops; existing older HTML prototypes are not affected, so $Tabs may need to be updated manually if desired.