Various unusual values for integer-type parameters to the Action API will no longer be accepted. Acceptable values will consist of an optional sign (ASCII `+` or `-`) followed by 1 or more ASCII digits.

Values that were formerly allowed, and will now result in a "badinteger" error, include:
Most clients should already be using correct formats, unless they are taking direct user input without validation.

This change will most likely go out to Wikimedia wikis with 1.35.0-wmf.19. See https://www.mediawiki.org/wiki/MediaWiki_1.35/Roadmap for a schedule.

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Brad Jorsch (Anomie)
Senior Software Engineer
Wikimedia Foundation