Deprecated APIs — Sphinx documentation

On developing Sphinx, we are always careful to the compatibility of our APIs. But, sometimes, the change of interface are needed for some reasons. In such cases, we’ve marked them as deprecated. And they are kept during the two major versions (for more details, please see Deprecation policy).
The following is a list of deprecated interfaces.
sphinx.io (entire module)
docutils.io or standard Python I/O
sphinx.builders.Builder.app
sphinx.environment.BuildEnvironment.app
sphinx.transforms.Transform.app
sphinx.transforms.post_transforms.SphinxPostTransform.app
sphinx.events.EventManager.app
sphinx.builders.singlehtml.SingleFileHTMLBuilder.fix_refuris
sphinx.util.FilenameUniqDict
sphinx.util.DownloadFiles
sphinx.ext.intersphinx.normalize_intersphinx_mapping
sphinx.ext.intersphinx.validate_intersphinx_mapping
sphinx.testing.util.strip_escseq
sphinx.util.console.strip_colors
Old-style Makefiles in sphinx-quickstart and the -M, -m, --no-use-make-mode, and --use-make-mode options
Vendoring the old style Makefile templates
sphinx.ext.autodoc.preserve_defaults.get_function_def()
N/A (replacement is private)
sphinx.builders.html.StandaloneHTMLBuilder.css_files
sphinx.builders.html.StandaloneHTMLBuilder.script_files
sphinx.builders.html.Stylesheet
sphinx.application.Sphinx.add_css_file()
sphinx.builders.html.JavaScript
sphinx.application.Sphinx.add_js_file()
sphinx.util.split_into
sphinx.util.split_index_msg
sphinx.util.index_entries.split_index_msg
sphinx.util.osutil.cd
sphinx.util.save_traceback
sphinx.util.exceptions.save_traceback
sphinx.util.format_exception_cut_frames
sphinx.util.exceptions.format_exception_cut_frames
sphinx.util.epoch_to_rfc1123
sphinx.util.http_date.epoch_to_rfc1123
sphinx.util.rfc1123_to_epoch
sphinx.util.http_date.rfc1123_to_epoch
sphinx.util.status_iterator
sphinx.util.display.status_iterator