to also identify fragments in plain text documents using regular expressions, with the keyword "match". They also describe a prototype implementation as an extension for the Firefox browser. For example, the following would find the case-insensitive text "RFC" anywhere in the document: http://example.com/document.txt#match=[rR][fF][cC] K. Yee of the Foresight Institute proposes "extended fragment identifiers" delimited with colons and a keyword to differentiate them from anchor identifiers. A text search fragment identifier with "fragment specification scheme" id "words" is the first proposal in this scheme. The following example would search a document for the first occurrence of the string "some context for a search term" and then highlight the words "search term": http://example.com/index.html#:words:some-context-for-a-(search-term) Text Fragments was proposed as a Draft Community Group Report in December 2021. This scheme uses the directive :~:text= to introduce the search term. https://en.wikipedia.org/wiki/History_of_computing#:~:text=The%20first%20recorded,Williams The above scheme was implemented in Chrome version 80. The LiveURLs project proposed a fragment identifier format for referring to a region of text within a page, of the form #FWS+C, where F is the length of the first word (up to five characters), W is the first word itself, S is the length of the selected text and C is a 32-bit CRC of the selected text. They implemented a variant of this scheme as an extension for the Firefox browser, using the form #LFWS+C, where L is the length of the fragment itself, in two hex digits. Linking to the word "Fragment" using the implemented variant would yield: http://example.com/index.html#115Fragm8+-52f89c4c Up until Firefox 5, Firefox supported XPath links such as #xpath:/html/body/div[3] which could be used in conjunction with a bookmarklet such as http://antimatter15.com/wp/2009/11/xpath-bookmark-bookmarklet/ to link within HTML documents that lacked proper IDs. This feature was removed as part of a code cleanup in https://bugzilla.mozilla.org/show_bug.cgi?id=457102 In ePub electronic book format, the EPUB Canonical Fragment Identifier (epubcfi, 2011-2017) defines a W3C/IDPF-standardized method for referencing arbitrary content using fragment identifiers to locate non-anchored text ranges via document structure and pattern matching. These dynamic deep links assist in locating content after text is updated and are used, for example, in Apple Books. See also URI normalization URL (Uniform Resource Locator) References External links W3C Media Fragments Working Group, establishing a URI syntax and semantics to address media fragments in audiovisual material (such as a region in an image or a sub-clip of a video) MediaMixer Community Portal collects presentations, tutorials, use cases and demonstrators related to use