There is a kind of agreement between the Republic of Germany and Austria, the website of the German consulate officially provides information on the procedures for the two countries. This link from the German consulate gives the answer to your question, and provides information in a table on the conditions of entry into Germany and Austria, for holders of blue 1951 convention documents, or holders of identity certificates. Yes, you will need a visa according to the simplified table. The official iata verification tool confirms the same thing:
https://canada.diplo.de/ca-en/consular-services/visa/convention-refugees/1308202
Also, outside the table, it is clearly stated:
Holders of a blue Canadian Travel Document (Convention of July 28th, 1951) do not need a visa for transit and/or short term stay (e.g. for tourism or business purposes for up to 90 days) in Germany. The travel document must be valid for at least 4 months counting from the date of entering Germany. It is recommended to book a direct flight to Germany without transiting through other Schengen countries. If you do transit through other Schengen countries, you have to apply for a visa at the Consulate at the specific country. For example, if you are travelling to Austria you have to apply for a visa.
Of course, it can be ''tempting'' to land in Germany, then to take a train or a bus in the schengen free zone... Except that the stamp you will have will only be valid in Germany. If you get checked in Austria without a visa, you risk being arrested + paying a fine + being returned either from where you came from or to Canada directly (this can also be considered an offence, and affect your future application for Canadian citizenship)
Here is a concrete case of someone who had tried to return to Switzerland from Germany by train with a Canadian RTD blue document convention 1951:
Moreover, there is an official document updated frequently by the European Commission, which indicates all the types of documents by issuing country, the countries of the European Union which accept them or not as documents... and those which grant or not a right visa-free entry. I'll look it up and post the link asap.
