Custom Button To Action Migration

Custom Button to Action Migration

This skill activates when a practitioner needs to migrate Classic Custom Buttons (especially JavaScript buttons, which are not supported in Lightning Experience) to Lightning Quick Actions, Screen Flow Actions, LWC Quick Actions, or other Lightning-native action surfaces.

Before Starting

Gather this context before working on anything in this domain:

• Inventory all custom buttons across all objects. Tooling API: SELECT Id, Name, EntityDefinition.QualifiedApiName, BehaviorType, ContentSource FROM WebLink. BehaviorType includes Detail, List, Mass; ContentSource includes URL, OnClickJavaScript, VisualforcePage, S Control.
• For each JavaScript button, capture the full OnClick JavaScript. The migration is heavily dependent on what the JS does — read each button before designing replacements.
• Confirm whether each button is currently invoked: usage data via WebLink is limited; consider deploying lightweight tracking (custom field on the user profile or feature consumption events) BEFORE deprecating to confirm low-usage buttons can be retired without replacement.
• Confirm Lightning UI is the primary user surface. JavaScript buttons continue to work in Salesforce Classic; if the org has both Classic and Lightning users, retain the Classic button and ADD a Lightning replacement (don't remove the Classic button if Classic users still need it).
• For URL buttons, confirm whether the linked URL is a relative Salesforce path (often broken in Lightning) or an absolute external URL (usually works as-is).

Core Concepts

1. Classic Button Type → Lightning Replacement

2. JavaScript Buttons Have NO Direct Lightning Equivalent

Salesforce explicitly does not support JavaScript Buttons in Lightning Experience. The button definition still exists in metadata (and continues to work in Classic), but in Lightning UI it does not render or fires only an "unsupported" message.

3. Three Lightning Action Surfaces

LWC Quick Actions are the modern preferred replacement for most non-trivial JavaScript buttons. Headless LWC Quick Actions specifically replace the "click button → confirmation alert → save" pattern.

4. List View / Mass Action Replacement

5. URL Button Translation Pitfalls

URL buttons in Lightning handle absolute external URLs cleanly. Relative paths break:

For relative paths, replace with a Quick Action that uses the Lightning navigation framework, not a URL.

Common Patterns

Pattern 1: JavaScript Button That Calls Apex → Headless LWC Quick Action

When to use: A Classic JS button that calls an Apex method, shows a confirmation/result, and refreshes the page. This is the most common JS button pattern.

How it works:

1. Identify the Apex class and method the JS button calls.
2. Convert the Apex method to @AuraEnabled (typically NOT cacheable since it performs side effects).
3. Build an LWC Quick Action with actionType=Action (headless mode) and target lightning__RecordAction.
4. The LWC's invoke() method calls the Apex imperatively, fires a toast for success/error, and dispatches RefreshRecordEvent from @salesforce/apex to refresh the page.
5. Configure the Quick Action in Setup → Object Manager → Buttons, Links, and Actions.
6. Add the Quick Action to the page layout (Lightning Actions section).

Why not the alternative: Screen Flow is also a valid replacement but adds a UI step (typically a confirmation screen) that users may not want for a simple "do it now" action.

Pattern 2: JavaScript Button with User Input → Screen Flow

When to use: A Classic JS button that prompts for input (a prompt() or a custom HTML form) and processes the result.

How it works:

1. Build a Screen Flow with the input fields the button collected.
2. Add an Action (Apex Invocable, Update Records, etc.) for the processing logic.
3. Configure as a Screen Flow Quick Action on the object.
4. Optional: add a confirmation screen for user feedback.

Why not the alternative: Building a custom LWC for a simple input form is overkill when Screen Flow handles it declaratively.

Pattern 3: JavaScript List Button → Mass Quick Action with LWC

When to use: A Classic JS list button that processes selected records via getRecordIds().

How it works:

1. Build an LWC component targeted at lightning__RecordAction with actionType=ScreenAction.
2. Expose @api recordIds (set automatically when invoked from a list).
3. The LWC's invoke() method (or the connectedCallback if always invoked once mounted) iterates this.recordIds and calls Apex with the collection.
4. Handle partial successes — some records may fail processing.
5. Configure as a List View Action in Setup.

Why not the alternative: Direct Apex Invocable Action from a Flow can also work, but loses the per-record progress UI an LWC can provide.

Pattern 4: URL Button to External System → Lightning URL Action

When to use: A Classic button that opens an external system URL with merge field substitution (e.g., a LinkedIn lookup, a CTI dial-out, a partner portal SSO).

How it works:

1. In Setup → Object Manager → Buttons, Links, and Actions, create a new Action with type "Custom Visualforce" or "URL".
2. Set the URL with merge fields: https://external.com/lookup?id={!Account.Id}&name={!Account.Name}.
3. Configure target window behavior (open in new tab vs replace current).
4. Add to the page layout.

Why not the alternative: For a simple URL navigation, an LWC Quick Action is overkill — URL Actions handle this natively.

Pattern 5: Coexistence — Retain Classic Button, Add Lightning Action

When to use: The org has both Classic and Lightning users. Removing the Classic button breaks Classic users; not adding the Lightning equivalent breaks Lightning users.

How it works:

1. Keep the Classic Custom Button as-is (works in Classic).
2. Build the Lightning Quick Action / LWC Quick Action / Screen Flow Action equivalent.
3. Both surface independently per UI mode.
4. Eventually, when all users are on Lightning, retire the Classic button.

Why not the alternative: Removing the Classic button before all users have moved to Lightning breaks production for Classic users immediately. Coexistence is the safe path during the transition window.

Decision Guidance

Recommended Workflow

Step-by-step instructions for an AI agent or practitioner working on this task:

1. Inventory custom buttons. Run the Tooling API query for WebLink. Group by BehaviorType and ContentSource. Read each JS button's OnClick body and capture what it does (Apex call, navigation, alert, DOM manipulation).
2. Categorize each button by pattern. Apply the Decision Guidance table. Most JS buttons fall into Pattern 1 (Apex call) or Pattern 2 (input prompt). URL buttons usually map cleanly to Pattern 4.
3. Audit usage. Confirm which buttons are actively used. Buttons that haven't been invoked in 6+ months should be retired without replacement (validated with the user-team).
4. Build the Lightning replacements. Implement per-pattern. Test each against the same scenarios the original button served.
5. Configure on page layouts and list views. Each Lightning Action must be added to relevant page layouts (Lightning Actions section) or list view button bars.
6. Test in sandbox with users from each affected profile. Specifically: do users find the new action where they expect it? Does the action's UX match the original's intent?
7. Phased production rollout with audit log. Coexistence first (keep Classic, add Lightning); monitor adoption via the Last_Action_Source__c field. Maintain a Custom_Button_Migration_Log__c mapping (Classic name → Lightning replacement → status). Retire Classic buttons when adoption hits the agreed threshold (typically ≥95% Lightning over 30 days).

Review Checklist

Run through these before marking work in this area complete:

• Every Classic Custom Button has a documented decision: replaced (with what), retained for Classic only, or retired
• JavaScript buttons that called Apex have been replaced with Headless or Screen LWC Quick Actions (or Screen Flow)
• URL buttons with absolute external URLs are mapped to Lightning URL Actions
• URL buttons with relative Salesforce paths are mapped to NavigationMixin-based Quick Actions
• List buttons that processed selected records have been replaced with Mass Quick Actions
• All Lightning replacements are added to relevant page layouts and list views
• User-acceptance testing: representative users from each affected profile confirm the action is discoverable and works as expected
• Mobile testing: any action that should work in Salesforce Mobile App has been verified on a real mobile device
• Coexistence period: original Classic button remains in place during the transition for Classic users
• Audit log of original button → Lightning replacement is committed to source control
• Apex methods called from Lightning replacements are @AuraEnabled with appropriate with sharing and FLS enforcement

Salesforce-Specific Gotchas

Non-obvious platform behaviors that cause real production problems:

1. JavaScript buttons silently render as nothing in Lightning Experience. A user navigating Lightning sees the button's place in the page layout — but the button doesn't render. There's no error message, no "this button isn't supported" indicator. Users assume the action is missing entirely. Audit page layouts for JS buttons and either replace them or flag to users that they're Classic-only.

2. Mass Action limit on records is 200 by default. A list view Mass Action that operates on selected records is governor-limited. Selecting 500 records and invoking a Mass Action processes only the first 200. Users notice silently (the unselected 300 just don't get the action applied). For Mass Actions on larger collections, design a Flow with batch processing or an async Apex job.

3. {!Account.Id} URL merge fields don't work the same way in all Lightning Action types. Lightning URL Actions support some merge fields, but the {!Object.Field} syntax differs from the Classic Custom Button merge field syntax in subtle ways. Quick Actions of type "URL" use a slightly different merge syntax than Classic. Test each merge field after migration.

4. Quick Actions invoked from a Console subtab don't navigate the same way as standard Lightning. In Service Cloud Console, a Quick Action that uses NavigationMixin.Navigate({type: 'standard__recordPage'}) opens the navigation in the console workspace — sometimes as a new tab, sometimes replacing the current tab, depending on the action's launch context. If the original button assumed a specific navigation behavior, test in Console mode explicitly.

5. List View Actions don't appear if the list view filter doesn't match any records. A Mass Quick Action requires at least one selectable record. Empty list views hide the action entirely. Users assume the action is missing for that list view, when actually no records match the filter.

6. window.opener and cross-window communication patterns from Classic JS don't translate. Some Classic JS buttons opened a popup window, then communicated back to the parent via window.opener.location.reload(). LWC and Lightning Quick Actions have no equivalent — windows are sandboxed differently. Re-architect these flows as Quick Actions that complete in the same context (no popups).

7. PageReference redirects from Classic Apex callbacks don't work in Lightning Quick Actions. A Classic JS button that called sforce.apex.execute and the Apex method returned a PageReference — Classic followed the redirect. In Lightning, the redirect is ignored. Re-architect: Apex returns data; LWC explicitly navigates via NavigationMixin after the call resolves.

8. Hard-coded record IDs in JS buttons don't translate to merge fields cleanly. Some JS buttons hardcoded record IDs (anti-pattern) for "demo" records or admin actions. The migration is the moment to remove the hardcoded IDs (use Custom Settings, Custom Metadata, or proper record-context resolution). Quick Actions and Flows have no equivalent for "always operate on record X regardless of context."

Output Artifacts

Related Skills

• admin/global-actions-and-quick-actions — Use for new Quick Action / Global Action design (post-migration)
• lwc/lwc-quick-actions — Use for designing LWC Quick Actions in detail (Headless vs Screen)
• flow/screen-flows — Use for designing Screen Flow Actions
• lwc/visualforce-to-lwc-migration — Use when buttons reference Visualforce pages being migrated
• apex/apex-security-patterns — Use when Apex methods called from new Quick Actions need their sharing keyword and CRUD/FLS enforcement designed correctly
• admin/lightning-app-builder-advanced — Use for placing Quick Actions on Lightning Record Pages