)]}'
{"id": 6534495085920256, "name": "Parse processing instructions in HTML", "summary": "Processing instructions (syntax: <?target data>) are an existing DOM construct, exposed in XML, that allows node objects that are not elements but can have some semantic meaning for the processing of a document.\n\nProcessing instructions are parsed by the HTML parser, and receive an attribute API similar to elements to mutate their data.\n", "markdown_fields": [], "blink_components": ["Blink>HTML>Parser"], "star_count": 99, "search_tags": [], "created": {"by": "nrosenthal@chromium.org", "when": "2026-02-03 12:39:06.301717"}, "updated": {"by": "nrosenthal@chromium.org", "when": "2026-06-22 15:02:37.957052"}, "category": "DOM", "category_int": 5, "feature_notes": "Note: this is shipped as part of https://chromestatus.com/feature/5111042975465472", "web_feature": "html", "is_official_web_feature": true, "webdx_usecounter_enum": null, "enterprise_feature_categories": [], "enterprise_product_category": 0, "is_releasenotes_content_reviewed": false, "is_releasenotes_publish_ready": false, "stages": [{"id": 4946759761657856, "created": "2026-02-03 12:39:06.773627", "feature_id": 6534495085920256, "stage_type": 110, "display_name": null, "pm_emails": [], "tl_emails": [], "ux_emails": [], "te_emails": [], "intent_thread_url": null, "announcement_url": null, "experiment_goals": null, "experiment_risks": null, "origin_trial_id": null, "origin_trial_feedback_url": null, "ot_action_requested": false, "ot_approval_buganizer_component": null, "ot_approval_buganizer_custom_field_id": null, "ot_approval_criteria_url": null, "ot_approval_group_email": null, "ot_chromium_trial_name": null, "ot_description": null, "ot_display_name": null, "ot_documentation_url": null, "ot_emails": [], "ot_feedback_submission_url": null, "ot_has_third_party_support": false, "ot_is_critical_trial": false, "ot_is_deprecation_trial": false, "ot_owner_email": null, "ot_requester_email": null, "ot_require_approvals": false, "ot_use_counter_bucket_number": null, "ot_webfeature_use_counter": null, "extensions": [], "experiment_extension_reason": null, "ot_stage_id": null, "finch_url": null, "rollout_milestone": null, "rollout_platforms": [], "rollout_details": null, "rollout_impact": 2, "rollout_stage_plan": null, "enterprise_policies": [], "desktop_first": null, "android_first": null, "ios_first": null, "webview_first": null, "desktop_last": null, "android_last": null, "ios_last": null, "webview_last": null}, {"id": 4743991402823680, "created": "2026-02-03 12:39:06.832443", "feature_id": 6534495085920256, "stage_type": 120, "display_name": null, "pm_emails": [], "tl_emails": [], "ux_emails": [], "te_emails": [], "intent_thread_url": "https://groups.google.com/a/chromium.org/d/msgid/blink-dev/6981ee47.050a0220.baa59.0100.GAE%40google.com", "announcement_url": null, "experiment_goals": null, "experiment_risks": null, "origin_trial_id": null, "origin_trial_feedback_url": null, "ot_action_requested": false, "ot_approval_buganizer_component": null, "ot_approval_buganizer_custom_field_id": null, "ot_approval_criteria_url": null, "ot_approval_group_email": null, "ot_chromium_trial_name": null, "ot_description": null, "ot_display_name": null, "ot_documentation_url": null, "ot_emails": [], "ot_feedback_submission_url": null, "ot_has_third_party_support": false, "ot_is_critical_trial": false, "ot_is_deprecation_trial": false, "ot_owner_email": null, "ot_requester_email": null, "ot_require_approvals": false, "ot_use_counter_bucket_number": null, "ot_webfeature_use_counter": null, "extensions": [], "experiment_extension_reason": null, "ot_stage_id": null, "finch_url": null, "rollout_milestone": null, "rollout_platforms": [], "rollout_details": null, "rollout_impact": 2, "rollout_stage_plan": null, "enterprise_policies": [], "desktop_first": null, "android_first": null, "ios_first": null, "webview_first": null, "desktop_last": null, "android_last": null, "ios_last": null, "webview_last": null}, {"id": 5712532331429888, "created": "2026-02-03 12:39:06.947562", "feature_id": 6534495085920256, "stage_type": 130, "display_name": null, "pm_emails": [], "tl_emails": [], "ux_emails": [], "te_emails": [], "intent_thread_url": null, "announcement_url": null, "experiment_goals": null, "experiment_risks": null, "origin_trial_id": null, "origin_trial_feedback_url": null, "ot_action_requested": false, "ot_approval_buganizer_component": null, "ot_approval_buganizer_custom_field_id": null, "ot_approval_criteria_url": null, "ot_approval_group_email": null, "ot_chromium_trial_name": null, "ot_description": null, "ot_display_name": null, "ot_documentation_url": null, "ot_emails": [], "ot_feedback_submission_url": null, "ot_has_third_party_support": false, "ot_is_critical_trial": false, "ot_is_deprecation_trial": false, "ot_owner_email": null, "ot_requester_email": null, "ot_require_approvals": false, "ot_use_counter_bucket_number": null, "ot_webfeature_use_counter": null, "extensions": [], "experiment_extension_reason": null, "ot_stage_id": null, "finch_url": null, "rollout_milestone": null, "rollout_platforms": [], "rollout_details": null, "rollout_impact": 2, "rollout_stage_plan": null, "enterprise_policies": [], "desktop_first": null, "android_first": null, "ios_first": null, "webview_first": null, "desktop_last": null, "android_last": null, "ios_last": null, "webview_last": null}, {"id": 5387149132300288, "created": "2026-02-03 12:39:07.002518", "feature_id": 6534495085920256, "stage_type": 140, "display_name": null, "pm_emails": [], "tl_emails": [], "ux_emails": [], "te_emails": [], "intent_thread_url": null, "announcement_url": null, "experiment_goals": null, "experiment_risks": null, "origin_trial_id": null, "origin_trial_feedback_url": null, "ot_action_requested": false, "ot_approval_buganizer_component": null, "ot_approval_buganizer_custom_field_id": null, "ot_approval_criteria_url": null, "ot_approval_group_email": null, "ot_chromium_trial_name": null, "ot_description": null, "ot_display_name": null, "ot_documentation_url": null, "ot_emails": [], "ot_feedback_submission_url": null, "ot_has_third_party_support": false, "ot_is_critical_trial": false, "ot_is_deprecation_trial": false, "ot_owner_email": null, "ot_requester_email": null, "ot_require_approvals": false, "ot_use_counter_bucket_number": null, "ot_webfeature_use_counter": null, "extensions": [], "experiment_extension_reason": null, "ot_stage_id": null, "finch_url": null, "rollout_milestone": null, "rollout_platforms": [], "rollout_details": null, "rollout_impact": 2, "rollout_stage_plan": null, "enterprise_policies": [], "desktop_first": null, "android_first": null, "ios_first": null, "webview_first": null, "desktop_last": null, "android_last": null, "ios_last": null, "webview_last": null}, {"id": 6153704493416448, "created": "2026-02-03 12:39:07.052658", "feature_id": 6534495085920256, "stage_type": 150, "display_name": null, "pm_emails": [], "tl_emails": [], "ux_emails": [], "te_emails": [], "intent_thread_url": "https://groups.google.com/a/chromium.org/d/msgid/blink-dev/69cbb13f.2b0a0220.5f79f.0391.GAE%40google.com", "announcement_url": null, "experiment_goals": "Changing the parser behavior to recognize processing instructions might uncover web compatibility issues in certain websites (though hopefully not!). We want to uncover them early in case it affects the shape of the API.\n\nNote that this is a finch (to 1% stable) rather than an OT.", "experiment_risks": "This experiment might uncover bugs. But it's not an origin trial, and we can turn it off and existing websites should not rely on it.", "origin_trial_id": null, "origin_trial_feedback_url": null, "ot_action_requested": false, "ot_approval_buganizer_component": null, "ot_approval_buganizer_custom_field_id": null, "ot_approval_criteria_url": null, "ot_approval_group_email": null, "ot_chromium_trial_name": null, "ot_description": null, "ot_display_name": null, "ot_documentation_url": null, "ot_emails": [], "ot_feedback_submission_url": null, "ot_has_third_party_support": false, "ot_is_critical_trial": false, "ot_is_deprecation_trial": false, "ot_owner_email": null, "ot_requester_email": null, "ot_require_approvals": false, "ot_use_counter_bucket_number": null, "ot_webfeature_use_counter": null, "extensions": [], "experiment_extension_reason": null, "ot_stage_id": null, "finch_url": null, "rollout_milestone": null, "rollout_platforms": [], "rollout_details": null, "rollout_impact": 2, "rollout_stage_plan": null, "enterprise_policies": [], "desktop_first": null, "android_first": null, "ios_first": null, "webview_first": null, "desktop_last": null, "android_last": null, "ios_last": null, "webview_last": null}, {"id": 4686611512164352, "created": "2026-02-03 12:39:07.182619", "feature_id": 6534495085920256, "stage_type": 160, "display_name": null, "pm_emails": [], "tl_emails": [], "ux_emails": [], "te_emails": [], "intent_thread_url": "https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAJn%3DMYbffHZ2XgpmXcx3RVqZ6UEZOXFxSJ-GzVAdt0kQUw-k3Q%40mail.gmail.com", "announcement_url": null, "experiment_goals": null, "experiment_risks": null, "origin_trial_id": null, "origin_trial_feedback_url": null, "ot_action_requested": false, "ot_approval_buganizer_component": null, "ot_approval_buganizer_custom_field_id": null, "ot_approval_criteria_url": null, "ot_approval_group_email": null, "ot_chromium_trial_name": null, "ot_description": null, "ot_display_name": null, "ot_documentation_url": null, "ot_emails": [], "ot_feedback_submission_url": null, "ot_has_third_party_support": false, "ot_is_critical_trial": false, "ot_is_deprecation_trial": false, "ot_owner_email": null, "ot_requester_email": null, "ot_require_approvals": false, "ot_use_counter_bucket_number": null, "ot_webfeature_use_counter": null, "extensions": [], "experiment_extension_reason": null, "ot_stage_id": null, "finch_url": null, "rollout_milestone": null, "rollout_platforms": [], "rollout_details": null, "rollout_impact": 2, "rollout_stage_plan": null, "enterprise_policies": [], "desktop_first": 150, "android_first": 150, "ios_first": null, "webview_first": 150, "desktop_last": null, "android_last": null, "ios_last": null, "webview_last": null}], "accurate_as_of": "2026-06-22 15:02:37.957052", "creator_email": "nrosenthal@chromium.org", "updater_email": "nrosenthal@chromium.org", "owner_emails": ["nrosenthal@chromium.org", "foolip@chromium.org"], "editor_emails": [], "cc_emails": [], "spec_mentor_emails": [], "unlisted": false, "deleted": false, "editors": [], "cc_recipients": [], "spec_mentors": [], "creator": "nrosenthal@chromium.org", "feature_type": "New or changed feature", "feature_type_int": 0, "intent_stage": "None", "intent_stage_int": 0, "active_stage_id": 4686611512164352, "bug_url": "https://issues.chromium.org/issues/481087638", "launch_bug_url": null, "new_crbug_url": "https://bugs.chromium.org/p/chromium/issues/entry?components=Blink>HTML>Parser&blocking=481087638&cc=nrosenthal@chromium.org,foolip@chromium.org", "screenshot_links": [], "first_enterprise_notification_milestone": 147, "enterprise_impact": 2, "breaking_change": false, "confidential": false, "shipping_year": 2026, "flag_name": null, "finch_name": "HTMLProcessingInstruction", "non_finch_justification": null, "ongoing_constraints": "None", "rollout_plan": 0, "rollout_plan_displayname": "Will ship enabled for all users", "motivation": "The work on out of order streaming showed that defining declarative ranges with elements is insufficient, and there's need to be a \"lighter\" declarative way to denote ranges, that doesn't e.g. affect CSS relationships.\n\nThis seems to unlock some future use-cases, such as declaratively denoting CSS custom highlights, and controlling the streaming/buffering of an HTML response.\n", "devtrial_instructions": null, "activation_risks": null, "measurement": null, "availability_expectation": null, "adoption_expectation": null, "adoption_plan": null, "initial_public_proposal_url": "https://github.com/WICG/webcomponents/issues/1116", "explainer_links": ["https://github.com/WICG/declarative-partial-updates/blob/main/patching-explainer.md#proposed-markup"], "requires_embedder_support": false, "spec_link": "https://github.com/whatwg/html/pull/12118", "api_spec": true, "automation_spec": false, "interop_compat_risks": "This feature changes the HTML parser to recognize XML processing instruction syntax, which was previously parsed as (bogus) comments. Querying HA showed that this is relatively safe, specifically as it doesn't parse xml-stylesheet and special characters like $.", "all_platforms": true, "all_platforms_descr": null, "non_oss_deps": null, "anticipated_spec_changes": null, "security_risks": null, "ergonomics_risks": null, "wpt": true, "wpt_descr": "https://wpt.fyi/results/html/syntax/parsing/parse-processing-instruction.tentative.html?label=master&label=experimental&aligned&q=processing-instruction", "webview_risks": null, "devrel_emails": ["devrel-chromestatus-all@google.com"], "debuggability": null, "doc_links": [], "sample_links": [], "prefixed": null, "tags": [], "tag_review": "https://github.com/w3ctag/design-reviews/issues/1134", "tag_review_status": "Issues addressed", "tag_review_status_int": 3, "security_review_status": "Pending", "security_review_status_int": 1, "privacy_review_status": "Pending", "privacy_review_status_int": 1, "security_continuity_id": null, "security_launch_issue_id": null, "updated_display": null, "resources": {"samples": [], "docs": []}, "comments": "Note: this is shipped as part of https://chromestatus.com/feature/5111042975465472", "ff_views": 5, "safari_views": 5, "web_dev_views": 4, "browsers": {"chrome": {"bug": "https://issues.chromium.org/issues/481087638", "blink_components": ["Blink>HTML>Parser"], "devrel": ["devrel-chromestatus-all@google.com"], "owners": ["nrosenthal@chromium.org", "foolip@chromium.org"], "origintrial": false, "prefixed": null, "flag": false, "status": {"text": "Proposed", "val": 2, "milestone_str": "Proposed"}, "announced": true, "desktop": 150, "android": 150, "webview": 150, "ios": null}, "ff": {"view": {"url": "https://github.com/mozilla/standards-positions/issues/1369", "notes": null, "text": "Positive", "val": 3}}, "safari": {"view": {"url": "https://github.com/WebKit/standards-positions/issues/628", "notes": null, "text": "Support", "val": 3}}, "webdev": {"view": {"text": "No signals", "val": 4, "url": null, "notes": null}}, "other": {"view": {"text": null, "val": null, "url": null, "notes": null}}}, "standards": {"spec": "https://github.com/whatwg/html/pull/12118", "maturity": {"text": "Specification currently under development in a Working Group", "short_text": "Working draft", "val": 4}}, "is_released": false, "is_enterprise_feature": false, "experiment_timeline": null, "ai_test_eval_report": null, "ai_test_eval_run_status": null, "ai_test_eval_status_timestamp": null}