What if France occupy Formosa and the Pescadores in the aftermath of the Sino-French War? They were pressured into leaving them up by the British in OTL, since the shaken government that replaced Ferry after the Tonkin Affair wasn't willing to haggle for them.
So let's assume that the Tonkin Affair doesn't happen; the French commanders in Tonkin don't send an early, pessimistic report about the front's status, and Ferry's government doesn't fall. Courbet holds onto Formosa and the Pescadores, and doesn't budge when the British tell him to. Ferry reminds the United Kingdom about the millstone of the Egyptian occupation, and the British grudgingly agree to allow France to retain the islands, as long as, say, the Pescadores are not fortified in any way.
How do things develop from here?
So let's assume that the Tonkin Affair doesn't happen; the French commanders in Tonkin don't send an early, pessimistic report about the front's status, and Ferry's government doesn't fall. Courbet holds onto Formosa and the Pescadores, and doesn't budge when the British tell him to. Ferry reminds the United Kingdom about the millstone of the Egyptian occupation, and the British grudgingly agree to allow France to retain the islands, as long as, say, the Pescadores are not fortified in any way.
How do things develop from here?