1398401 - Assertion failure: !slots->mCustomElementData (Custom element data may not be changed once set.), at dom/base/Element.cpp:4210

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect, P1)

Description

[Bob Clary [:bc] (inactive)]

Attachment: Windows assertion log

[Tracking Requested - why for this release]:

1. https://www.gcflearnfree.org/powerpoint2013/modifying-themes/1/

2. Assertion failure: !slots->mCustomElementData (Custom element data may not be changed once set.), at z:/build/build/src/dom/base/Element.cpp:4210

Windows/Linux Nightly 57 but not Beta 56 -> regression

Comment 1

[Hsin-Yi Tsai (she/her) [:hsinyi]]

Hi John, the assertion was added in bug 1347634, which was landed in 55, could you please check what has been done in 57 that caused this regression? Thank you.

Comment 2

[John Dai[:jdai]]

Attachment: patch, v1

The reason is we missed add a preference check when we're going to setup custom element v0[1]. This code will be changed to v1 version by bug 1378079. Hence, I add IsWebComponentsEnabled() which is a v0 preference check for this bug.

Try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=203aeededc60a680725b8bc54bbcf1866b3ea0fd&filter-tier=1&group_state=expanded

[1] https://searchfox.org/mozilla-central/rev/51eae084534f522a502e4b808484cde8591cb502/parser/html/nsHtml5TreeOperation.cpp#447-450

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/48448bff8f92
Add preference check for custom element setup. r=smaug

Comment 4

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/48448bff8f92