Experimental features: Fixes for cssletterspacing

[hamishwillee]

The experimental features page has a bunch of errors, reported in #36742. This fixes the following ones:

• layout.css.letter-spacing.model is also enabled in developer - https://searchfox.org/mozilla-central/source/modules/libpref/init/StaticPrefList.yaml#9419
• media.setsinkid.enabled - deleted the section. This was enabled in FF116 (and documented). Not enabled for android, but it isn't an experimental feature in android, it is just not implemented.
• security.insecure_connection_text_* and browser.urlbar.trim preferences were enabled in nightly in FF121 https://bugzilla.mozilla.org/show_bug.cgi?id=1853418 - this updates the releases and also adds info about the browser.urlbar.trim preference ("somewhat related")
• layout.css.relative-color-syntax.enabled - removed section as support added FF128 (and documented)
• layout.css.font-tech.enabled - removed section - tech() feature added in 106
• layout.css.backdrop-filter.enabled - CSS backdrop-filter - removed section as feature added in FF103
• layout.css.page-orientation.enabled removed section page-orientation descriptor added in FF122
• layout.css.zoom.enabled - removed section - CSS zoom added in FF126 (and documented)
• layout.css.text-wrap-balance.enabled - remove section - stuff added in 121 (and documented 29787 text wrap browser-compat-data#21311)
• layout.css.prefixes.transitions removes (supported in FF126). UPdated layout.css.prefixes.transforms as no longer supported in Nightly - test didn't work.
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[github-actions]

Preview URLs

• /en-US/docs/Mozilla/Firefox/Experimental_features

External URLs (3)

URL: /en-US/docs/Mozilla/Firefox/Experimental_features
Title: Experimental features in Firefox

• https://bugzil.la/1853418 (1 time) (Note! This may be a new URL 👀)
• https://bugzil.la/1855763 (1 time) (Note! This may be a new URL 👀)
• https://bugzil.la/1886134 (1 time) (Note! This may be a new URL 👀)

(comment last updated: 2024-12-03 05:45:15)

[hamishwillee]

Note, they tried to get this in in FF120, but when zoom when in in FF126 it broke too much. So this still exists, but it is off by default in nightly for the moment.

[hamishwillee]

@bsmth This should all be good, but you can get more info on the changes by cross referencing here #36742

[bsmth]

@bsmth This should all be good, but you can get more info on the changes by cross referencing here #36742

Nicely done, thanks a lot. I'll take a look shortly

[bsmth]

All looking good to me, maybe we can add something for page-orientation in a follow-up because the removal is correct here.

Thank you! 👍🏻

[hamishwillee]

maybe we can add something for page-orientation in a follow-up because the removal is correct here.

My take on release notes is that people are interested in the release month, but by the third month after release only weirdos like us care. I'll be updating anything in the last 6 releases, but no worth it after that.

I did however fix up BCD mdn/browser-compat-data#25299 because that has real and ongoing value.

[hamishwillee]

PS Thanks for the review. Nice to start the next lot with a clean slate. EDITED Except weirdly it wouldn't let me merge at first even with your approval - sorted on a second refresh. Crazy! Thanks again.