Nor is the first paragraph after any heading unless that heading is itself indented, as they may be at the fifth and sixth levels. 6 Footnotes Footnotes are to be used rather than endnotes. Footnotes begin with a capital letter, except when the first word is a conventionally lower case abbreviation. Avoid the constant repetition of 'See'. Footnotes impliedly include that instruction to the reader.
Footnotes end with a full-stop, unless they happen to end with a question mark or exclamation mark.
In many of the examples above there is no stop. That is because the examples are neutral as to their position or juxtaposition in the note. Footnotes are not for chat, not for conducting interesting counter-arguments. They are for locating sources relied upon in the text, and, in moderation, for identifying supplementary sources. There is no point in dense notes inches deep.