The more usual, what you might call “orthodox” view among Protestants is that miracles have ceased (thus the term “cessationist”), and they ridicule Catholics for believing that they have happened in recent centuries along with their many other accusations of superstition. So it does not seem like Reformed Christians have an abundant testimony of miracles. I had read prior on a Protestant blog dealing with this subject that there are reports of miracles in relation to John Knox and Martin Luther. However, I just googled it, and I can’t find anything to validate that claim. Martin Luther himself was a cessationist, which would be absurd if he was going around raising the dead. Closest I found was that John Knox thought he was a prophet equal in every way to the Old Testament prophets on the basis of his “strong interior conviction” and that he liked to make predictions about future events. Nevertheless, there was nothing about his love for predicting things that went beyond a natural ability. So in short, the more traditional Protestants do not believe in miracles nor claim to have worked them.
Other Protestants, especially Charismatic ones, are more likely to believe in continuing miracles and that their coreligionists have experienced miracles. I have seen stories of individual testimonies online. I suppose you’d have to judge for yourself whether those are true.
St. Francis de Sales focuses on miracles quite a bit in The Catholic Controversy. One of his big arguments is that authorities in the Church must have “mission” from God (i.e. they must be sent by God). This can be either immediate and extraordinary (as Moses was sent directly by God) or mediate and ordinary (as a Catholic priest is sent by the Church’s ordinary authority, but which derives from the Apostles who were sent immediately by Christ). He further argues that if the Reformers were sent immediately by God, they must of necessity have the testimony of miracles to validate their mission, otherwise, no one would be obliged to listen to them.
My view is that God might work miracles outside of the Church, if it would not seem to validate falsehood. For instance, God might miraculously provide food for hungry pagans in it would not encourage idolatry. Or God might work miracles lending support to (non-Catholic) Christian missionaries in Muslim lands, even though what they are preaching is mixed with much error, in order that the name of Christ might not be blasphemed. Also, there can be things which have the appearance of the miracles but are not really miracles. Demons can work in ways that seem supernatural, but only God can work truly outside the natural order. For example, the Pharaoh’s magicians were able to do great feats, but these were undoubtedly not true miracles, but rather the work of demons. St. Paul also speaks of a Son of Perdition who will perform miraculous signs, but also calls them “lying wonders.”
