EXCLUSIVE: Rosenstein discussed invoking the 25th Amendment to oust Trump in the days after Comey was fired in May 2017. Rosenstein also discussed wearing a wire to secretly record his conversations with Trump. https://t.co/lq3iWOqM1r w/@adamgoldmanNYT

— Michael S. Schmidt (@nytmike) September 21, 2018

Addendum:
According to this news report, Rosenstein denies the report and adds:

Mr. Rosenstein disputed this account.

“The New York Times’s story is inaccurate and factually incorrect,” he said in a statement. “I will not further comment on a story based on anonymous sources who are obviously biased against the department and are advancing their own personal agenda. But let me be clear about this: Based on my personal dealings with the president, there is no basis to invoke the 25th Amendment.”

A Justice Department spokeswoman also provided a statement from a person who was present when Mr. Rosenstein proposed wearing a wire. The person, who would not be named, acknowledged the remark but said Mr. Rosenstein made it sarcastically.

In other words, yeah, it happened and people around me think Trump is unstable and deserving of the 25A.