Issue: #965 Status: IMPLEMENTED & VERIFIED (2026-09-24)

Legacy edit form gui/templates/dashio/issuetrackers/issueTrackerEdit.tpl:24-65 (displayCfgExample) puts an eye icon (fa-eye, tooltip show_hide_configuration_example) next to the Configuration field. Clicking it AJAX-loads lib/ajax/getissuetrackercfgtemplate.php?type=N and INJECTS the selected interface's $iname::getCfgTemplate() as a <pre><xmp> block into #cfg_example, or the localized messages:

• issuetracker_interface_not_implemented — interface class file is missing;
• issuetracker_invalid_type — type unknown OR disabled (getTestLinkType / getTypes() maps ENABLED types only).

Browser probe (legacy, pre-fix): ?type=15 → redmine template; ?type=999 → "Issue Tracker type 999 is unknown".

The modern screen dropped it — the Configuration field was a static textarea placeholder with no way to load the per-type template.

• api/issuetracker/index.php had no route serving the per-type template.
• issuetrackerView.html trackerModal had only the Configuration textarea; DOM probe #cfgExample absent; no eye helper.
• Legacy getissuetrackercfgtemplate.php semantics reproduced: it maps the type through tlIssueTracker::getTypes() (enabled-only, tlIssueTracker.class.php:150-160), resolves the interface via getImplementationForType() and probes the class file with stream_resolve_include_path() BEFORE any include — a missing interface never triggers the autoloader's include_once (thus never logs an E_WARNING into the events table).

BFF api/issuetracker/index.php — new route GET /api/issuetracker/index.php/cfg-template?type=N mirroring the legacy ajax:

• $mgr->getTypes() gating (isset($itt[$type])) → disabled/unknown types get {status:error, code:invalid_type, type:N} (getTypes parity — disabled types are "invalid" like legacy).
• stream_resolve_include_path($iname.'.class.php') probe → missing interface returns {status:error, code:interface_missing, iface:$iname} WITHOUT ever reaching the autoloader (no E_WARNING rows, legacy parity).
• Present class → require_once() (only if !class_exists($iname,false)) then {status:ok, type:N, template:$iname::getCfgTemplate()}.

The JSON BFF has no lang_get, so error codes are structured and the client localizes them via TLi18n interpolation ({type} / {iface}).

HTML gui/templates/issuetracker/issuetrackerView.html:

• Eye anchor #btnCfgExample (fa-eye, localized tooltip it.showHideConfigExample) beside the Configuration label.
• Hidden #cfgExampleOuter + #cfgExample <pre> block (max-height 220px, overflow auto, white-space:pre-wrap).
• JS loadCfgTemplate(done) — GETs /cfg-template?type=N, draws the raw template via textContent (xmp parity, no innerHTML — XSS-safe), or the localized it.msg.interfaceMissing / it.msg.invalidType / it.msg.errorTemplate.
• JS toggleCfgTemplate() — port of legacy displayCfgExample hide/show toggle.
• #editType change handler refreshes a SHOWN example (requested in #965: the cfg keys must follow the selected interface).
• hidden.bs.modal + showCreateModal() + editTracker() collapse the block on close/reset (legacy collapsed state parity).

i18n — new keys it.showHideConfigExample, it.cfgExample, it.msg.invalidType, it.msg.interfaceMissing, it.msg.errorTemplate added to ALL 10 locale bundles (en/ro/de/es/fr/it/ja/pt/ru/zh), each validated with python3 -m json.tool; key sets identical across bundles. Note: the JSON BFF mixed trailing comma concern was avoided — bundles re-validated after edit.

• Click eye (type=GitHub): #cfgExampleOuter shown with the github REST getCfgTemplate() block; second click hides it; re-open resets.
• Type change (create modal): eye shown → switch Type 25→15 → example auto-refreshes to the redmine template.

• Edit modal: opening an existing tracker (Redmine Tracker, type 15) + eye click → redmine template.

• Invalid type: parseInt('')→0 → client renders "Issue Tracker type 0 is unknown" (i18n it.msg.invalidType).
• Interface missing: BFF probe ?type=26 with trellorestInterface.class.php temporarily moved → 200 {"status":"error","code":"interface_missing","iface":"trellorestInterface"}, client renders "Issue Tracker interface trellorestInterface is not implemented/available". class restored after test.
• E_WARNING hygiene: the stream_resolve_include_path probe produced NO events E_WARNING rows for the missing-file test (old class_exists-based attempt logged 2 rows — measured, deleted; clean re-test shows only the LOGIN audit row). Also exercised the built-in-server 500 edge (a require_once fatal surfaced once during mid-edit; after the final clean code state the route is stable across repeated calls).
• Locale RO: ?locale=ro → modal title "Creaza Urmator Probleme", eye tooltip "Arată/Ascunde exemplu de configurare", example label "Exemplu de configurare", template loads normally.

• BFF parity: ?type=26 (file present) → ok + trello template; ?type=15 → ok + redmine template; ?type=10 (disabled) → invalid_type; ?type=999 → invalid_type. Regression: check-connection + meta/types (26) intact.
• Event Viewer / events table: no new Error/Warning; browser console clean (only the pre-existing a11y notice).

Appended to tmp/TLU_Test_Cases.md (Suite 965); CHANGELOG updated.

Status: DONE — closed in #965.