Also, mozilla::TextEditRules::CollapseSelectionToTrailingBRIfNeeded can improve performance since it uses nsIDOMNode.

Comment on attachment 8872238 [details] Bug 1368387 - Remove nsIDOMText usages from Editor. https://reviewboard.mozilla.org/r/143722/#review147416 ::: editor/libeditor/HTMLEditRules.cpp:6466 (Diff revision 1) > if (!sibling || !mHTMLEditor || !mHTMLEditor->IsVisBreak(sibling) || > TextEditUtils::HasMozAttr(GetAsDOMNode(sibling))) { > NS_ENSURE_STATE(mHTMLEditor); > newBRneeded = true; > } > - } else if (aOffset == (int32_t)strLength) { > + } else if (aOffset == (int32_t)node->Length()) { nit: I'd like you to use static_cast<int32_t>(node->Length()) here (but okay to do it in a new bug). ::: editor/libeditor/TextEditRules.cpp:460 (Diff revision 1) > - uint32_t length; > - rv = nodeAsText->GetLength(&length); > - NS_ENSURE_SUCCESS(rv, rv); > - > // nothing to do if we're not at the end of the text node > - if (selOffset != int32_t(length)) { > + if (selOffset != int32_t(selNode->Length())) { Same, but up to you.

Pushed by m_kato@ga2.so-net.ne.jp: https://hg.mozilla.org/integration/autoland/rev/29d7c9080594 Remove nsIDOMText usages from Editor. r=masayuki