Chrome 100 Could 'Break' Websites

John Lister's picture

Major browser developers are preparing to mitigate a quirky bug that could make some websites unavailable. It's a low key version of the Y2K/Millennium Bug problems of 1999.

By something of a coincidence, Google's Chrome, Mozilla's Firefox and Microsoft's Edge browsers will all be hitting version 100 in the coming months. While it's good to know they've continued to improve the browsers and fix bugs, that milestone brings its own problems.

Many websites include code to check the version number of the visitor's browser. They will then block the site from opening on older browsers which won't support key features on the site or could cause serious performance or security issues. That's particularly important for sites that deal with personal information.

Unfortunately it appears that some sites were coded with a lack of foresight and assume the browser version will always have two digits (before any decimal places). That means the browser will report it is running version 100 but the website will read it as version 10. That will usually be "outdated" enough to trigger problems such as a mistaken block.

Among the sites which had such issues in Google testing were HBO Go, T-Mobile and Yahoo, though the effects will vary. (Source:

Version 99 Forever

For the most part, the fix will need to come from site operators updating their code. However, Google and Mozilla are both trying workarounds.

Google says one option is for it to change Chrome so that it continues to label it as version 99 and then put the real version after the decimal point. For example, what's actually version 101.2 will be signaled as 99.1012. Whether that creates more problems is still under investigation.

Meanwhile Mozilla is instead trying out a solution that would effectively tell the browser to "fix" the problematic code in the website, something it already does for some security issues.

Y2K All Over Again

It's all reminiscent of the problems in 1999 when computer experts realized many applications and systems were set to store only the last two digits of dates and could cause problems by mistakenly reading the new year as 2000. A major computer engineering operation was so successful that many people mistakenly assumed the issue was overhyped as very little went wrong in reality.

A similar issue may arise in 2038. Most computers keep track of the date and time by measuring the number of seconds that have passed since a fixed point in 1970. Come 2038 that number will be bigger than older 32-bit systems can handle. Fortunately most such systems should be out of use by then, while there's enough time to fix the rest. (Source:

What's Your Opinion?

Are you surprised website developers took this shortcut? What are your memories of the Millennium Bug? Had you heard about the 2038 issue?

Rate this article: 
Average: 4.8 (8 votes)


LouisianaJoe's picture

I have been programming for 54 years, so I had to deal with these "unexpected" problems over the years.

My fix for the transition from 2 digit years to 4 was to write a date validation function that had a string containing the date as its argument. In my programs, anywhere I validated the date I changed it to call the new function. Initially, the year was valid if the 2 digit year was between 70 and 99 or less than 30. After converting the database to have 4 digit years, I only had to change the function and re-compile the programs using it. I may have left out a detail since that was 22 years ago.

Gurugabe's picture

There is a Chrome flag anyone can use to test this themselves. chrome://flags/#force-major-version-to-100
Try it, report it, let's get this stupid issue fixed for life.

As for the 32-bit extent of this, I do realize that there is a problem with that. I believe the initial Y2K fix was to push the 2 digit year up a few years as you pointed out. I am guessing the same will apply later, unless we go up to 100% 64-bit systems, to include the BIOS.

Doccus's picture

I suppose it's interesting that this post was published on 2 22 2022.. that many 2s won't happen again for 200 years, in the year 2220, and then two years later, in 2222. Oh, and p.s., hopefully quantum computers will have taken care of the millennial bug too