Zack Nelson, the man behind the JerryRigEverything channel, which has nearly 10 million subscribers on YouTube, posted a video on Tuesday showing the $1,799 device snapping at its antenna lines before its battery began smoking heavily enough to trigger a fire alarm in his workspace. The explosion occurred when Nelson attempted to straighten the phone after it had already fractured during the bend test, causing the battery layers to pinch together and short circuit.​​

“Surprisingly, in the decade that I’ve been durability testing phones, I have never had a smartphone explode before,” Nelson said in the video. “The Pixel 10 Pro Fold is the first phone to go up in smoke.”

The failure was particularly notable because the device broke at the same structural weak point that plagued its two predecessors. Both the original Pixel Fold and last year’s Pixel 9 Pro Fold snapped along antenna lines positioned near the hinge during similar tests. Nelson criticized Google for not addressing the design flaw despite two previous catastrophic failures.​

“Having the audacity to call the Pixel 10 Fold extremely durable during their launch event while not changing the antenna line locations from the previous two versions that catastrophically failed is an insult to tech enthusiasts everywhere,” he said.

“This is like Vader building a third Death Star with the exact same exhaust port, or Voldemort hiding all seven Horcruxes in Harry Potter’s closet,” Nelson added. “Henry Ford said the only real mistake is the one from which we learn nothing. And I’m not saying that Google hasn’t learned nothing, nor am I saying that a durability test is the only decision by which to base your phone buying experiences off of. But the definition of insanity is doing the same thing over and over and expecting different results​.”

Google had marketed the Pixel 10 Pro Fold as its most durable foldable yet, claiming the device could withstand more than a decade of folding and featuring the first IP68 rating for dust and water resistance on any foldable smartphone. The company also touted a redesigned gearless hinge that it said was twice as durable as the previous generation.​

However, Nelson’s testing raised questions about those durability claims. When he poured sand into the device’s hinge—a standard part of his dust resistance evaluation—the phone produced what he described as “disturbing crunching sounds,” suggesting particles had infiltrated the mechanism. “The screen is probably dust-proof,” Nelson said, “but the hinge definitely is not.”​

The battery explosion occurred due to thermal runaway, a chain reaction within lithium-ion batteries that happens when heat generation exceeds the battery’s ability to dissipate it. When Nelson bent the phone, the physical fracture along the antenna line pinched the battery’s internal layers together, causing a short circuit that released all of the battery’s stored energy in an uncontrolled burst.​

“The pouch-style lithium batteries are made up of long sheets of foil that are wrapped around each other,” Nelson explained in the video. “Since my phone physically fractured along the antenna line, we must have pinched the layers of the battery together, causing a short circuit, which immediately dumps all of its energy into a self-accelerating, uncontrolled thermal reaction.”

Thermal runaway typically occurs when battery temperatures reach 150 to 180 degrees Celsius, triggering exothermic reactions that can drive temperatures beyond 1,000 degrees Celsius. The phenomenon is self-perpetuating and nearly impossible to stop once it begins.​

Nelson noted that while his tests are extreme, he has subjected every mainstream smartphone made in the past decade to identical evaluations without ever experiencing a battery fire.​​

The Pixel 10 Pro Fold, which launched this fall, features Google’s new Tensor G5 processor manufactured using TSMC’s 3nm process, 16GB of RAM, and screens measuring 6.4 inches externally and 8 inches internally. The device is available starting at $1,799 for the 256GB model, but can cost up to $2,149 for 1 terabyte of storage.​

Google did not immediately respond to Fortune with regards to Nelson’s testing results.

Despite the dramatic failure in Nelson’s test, other reviewers have praised the Pixel 10 Pro Fold’s durability features under normal use conditions, particularly its IP68 rating. One reviewer took the device to a beach where it became covered in sand and partially submerged in saltwater but continued functioning afterward.​

Nelson ended his video by suggesting Google should relocate the antenna lines in future designs. “I would, however, recommend that before Google attempts anything else, they should relocate the antenna lines near the hinge or not,” he said. “Either way, I’ll be here next year to keep them in check.”

You can watch Nelson’s teardown of the Google Pixel 10 Pro Fold below. It lights on fire at the 7:25 mark:

For this story, Fortune used generative AI to help with an initial draft. An editor verified the accuracy of the information before publishing.