The Ontario Gazette

The Ontario Gazette is the official publication of the Government of Ontario, containing legislative decisions, proclamations of new statutes, all regulations made under Ontario statutes, and notices that must be made public. It's published every Saturday.

The table of contents doesn't appear to hold much genealogical promise. Here it is for Volume 152 Issue 29 | July 20 2019:

Publications under Part III (Regulations) of the Legislation Act, 2006
Government Notices Respecting Corporations
Government Notices — Other
Government Notices — Other (continued)
Applications to Provincial Parliament — Private Bills
Applications to Provincial Parliament
Corporation Notices
Other
Sale of Land for Tax Arrears by Public Tender
Publications under Part III (Regulations) of the Legislation Act, 2006

While the bulk of the content isn't of genealogical interest there are a few sections crammed with names:

• Over 100 persons listed under The Marriage Act registering, reregistering or cancelling registration to perform marriages.
• A four-page listing of name changes under the Change of Name Act.

Looking back to the issue for 12 August 2000, selected at random, there's a six-page name change list.

Publications are available online back to January 2000. Prior publications, back to 1868 are found at the Archives of Ontario and depository libraries. I suspect the content has changed substantially over the years. Maybe there's content relevant to your family history hidden in these obscure volumes?