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Shogo SENSUI (@1000ch)
● Engineering with a strong focus on
Web Standard technologies and
JavaScript
● Working on several stuff at Merpay,
Inc. Previously worked on starting
up of Merpay Frontend, leading a
revamp of Mercari Web, etc
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What is interop?
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Similar to compatibility, but in a broader sense
interop ==
interoperability
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As a result of interop improvement
● Users can have a better browsing experience
● Developers can have a better development experience
● Web as a platform can be more sustainable
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Interop 2021
● 2019 and 2020 insights were
reported to compile Compat
2021
● The 5 top focus areas in 2021
○ CSS Flexbox
○ CSS Grid
○ CSS position: sticky;
○ CSS aspect-ratio property
○ CSS Transforms
● Holiday Update: presents for
developers before the end of
the year
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Interop 2022
● Apple, Bocoup, Google, Igalia,
Microsoft, and Mozilla agreed
to work on Interop 2022
● The 15 areas of focus including:
○ CSS @layers
○ CSS contain property
○ element
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Why interop
matters?
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> In essence, the goal is to make the web
platform more usable and reliable for
developers, so that they can spend more
time building great web experiences instead
of working around browser inconsistencies.
Interop 2022: browsers working together to improve the web for developers
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If only browser X supports feature Y?
● Developers need to have a workaround for other browsers
a. They may want to ignore other browsers if they use feature Y
● Users can browse web pages easily using browser X
a. The share of browser X may increase if they have a good experience with feature Y
● (Business) impact of browser X become stronger
a. It may affect the development resource of browser vendors
b. It may affect the neutrality of web platform
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The state of browsers in Japan
● Internet Explorer 11 support
will end at 2022-06-15 🎉
● Some services started not to
support Firefox (PayPay Bank,
NHK+, etc) 🦊
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Possible approaches from developers?
● Developers are leaders in sustaining the health of the web
○ The web exists with web pages created by developers that work on every browser
○ Fundamentally speaking, the share of browser X increase if web pages only support
browser X
● Developers should follow the stable web standards
○ By developing web pages that follow the stable web standards
○ By reporting a bug that is incompatible with the stable spec
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Possible approaches from browser vendors?
● Vendors should reduce the complexity of web standards
○ By keeping APIs at lower level to delegate the complexity to applications
○ The complexity makes it difficult to implement a browser from scratch
● Vendors can try to fork existing browsers (Chromium, WebKit, Gecko)
○ Browser diversity is okay as long as it follows stable web standards
○ The problem is who pay for the cost of maintaining web platform