Like recent MacBooks, Apple's new MacBook Pros use its controversial "butterfly" keyboards. But amidst user complaints about how fragile they are, Apple added an interesting tweak to the 2018 machines: each key is now loaded a thin film of silicone inside, according to iFixit.

The rubberized layer fits under each keycap, and effectively cocoons the butterfly switches running inside from "the daily onslaught of microscopic dust," iFixit said in a Friday blog post.

Apple has said only that its new MacBook Pros contain a "third-generation" butterfly keyboard, which promises quieter typing. But iFixit isn't convinced the rubbery film is related to silencing your typing.

"In fact, Apple has a patent for this exact tech designed to "prevent and/or alleviate contaminant ingress," iFixit said.

Last month, Apple did announce that a "small percentage" of MacBook and MacBook Pro models had faulty keyboards, and offered free repairs. However, the company has refrained from getting specific about the exact issue. Apple is currently facing several class-action lawsuits over defects in its keyboard tech, so the company probably didn't want to admit too much wrongdoing, iFixit noted.

Nevertheless, critics say the problems almost certainly have to do with the company's butterfly keyboard tech, which Apple first introduced in 2015. Although the technology is designed to be ultra-thin and quiet, it can also be quite delicate. According to consumer complaints, individual keys can become stuck or unresponsive, sometimes due to the mere presence of dust. Not helping the matter is that fixing the problem can involve replacing the entire MacBook's keyboard.

So far, Apple hasn't commented on the new rubbery film in the laptops. But iFixit said it's going to test how durable it stands up to actual dust.