style/trailing-space

Removes spaces and tabs at the end of lines. A hard line break written as two or more spaces keeps them.

Style rule, fixed by format. Presets: recommended (warn). Dialects: all. Options: hardBreak, hardBreakSpaces, listItemEmptyLines, codeBlocks.

With { "hardBreak": "backslash" }, before, with two spaces after one:

Line one  
line two

After:

Line one\
line two

Option	Values	Default
hardBreak	"keep" or "backslash"	"keep"
hardBreakSpaces	An integer of at least 2	Keep existing count
listItemEmptyLines	A boolean	false
codeBlocks	A boolean	false

• hardBreak: "backslash" writes a hard line break of spaces as a backslash, so that it is visible in the source.
• hardBreakSpaces: writes an existing space-style hard break with exactly that many spaces; with 2, three spaces become two, as Prettier writes it. hardBreak: "backslash" takes precedence; where converting to a backslash is unsafe, the break stays. It never creates a break and leaves the protected Tab suffixes below intact.
• listItemEmptyLines: true keeps whitespace-only lines inside list items, including their existing indentation. Spaces that make no break elsewhere are removed, matching markdownlint's strict checking.
• codeBlocks: true reports trailing spaces and tabs in fenced and indented code without an edit. Code content always stays byte for byte as written. Opaque renderer regions still suppress ordinary findings; in particular, VitePress's indented code stays opaque.

Edge cases and advanced usage

Details:

• Blank space after a literal backslash stays when removing it would turn a continuing prose line into a hard line break, in paragraphs, headings, lists, and quotes. Blank space at the end of a paragraph or file can still be removed; hardBreak controls existing hard line breaks.
• A Tab followed by two or more spaces can mark a hard line break even where the primary Markdown reading has a soft line ending. In every dialect, that suffix stays exactly as written, including with hardBreak: "backslash". Ordinary trailing Tabs and spaces, and those on the last content line of a paragraph or heading, can still be removed where they have no rendered meaning.

Left as written: blank space that is content: in code blocks, except on their fence lines, and in HTML, math, front matter, Obsidian comments, code spans, and link titles and labels that span lines.

With "backslash": a break stays as spaces where a backslash would change what the line says: after another backslash, after a literal autolink such as www.example.com, which would take the backslash into its address, on the title line of an alert or callout, in a paragraph that starts like a link reference definition ([label]:), and on Forgejo and Gitea inside \(...\) math.

Dialect notes

In Obsidian:

• A list marker alone on its line keeps one space after it. Live Preview needs that separator to style the line as a list item, even when the item's text starts on the next line. Extra spaces and tabs are reduced to that one space where safe. Quoted markers and further markers on the same physical line get ordinary cleanup, because Live Preview reads them as text.
• A line of blank space that holds a tab or lies directly below an HTML block stays, because Reading view reads it as more of the block above it. So does blank space at the end of a footnote definition's last line, where a paragraph ends the definition, which Reading view shows before the footnote's backreference.
• The preceding paragraph's separator before a Tab-only continuation stays when it marks a hard break or keeps a backslash literal. A Tab that begins before an unquoted paragraph's content column does not continue that paragraph merely by advancing past the column. Quoted margins are handled conservatively, keeping a possibly removable separator.