WA multibyte alphabets render but never commit output (no text produced when steering)

[willwade]

What

Every WorldAlphabets alphabet with multi-byte symbols (Arabic, Hebrew, Amharic, Urdu, …) renders a weighted tree after the colour-token fix (da2e558) but produces no output when steered — dasher_get_output_text stays empty forever. WA ASCII alphabets (English) output fine; legacy v5 multibyte alphabets (Russian) output fine.

Evidence (engine-level probes, no fonts involved)

Identical steering program (fixed coordinates, hold, 100–1000 frames, turbo constant-time convention that reliably yields output for other alphabets):

Alphabet	Output	CSymbolNode::Do() calls
English with limited punctuation	'I'	fires
English (WorldAlphabets)	'w'	fires
Russian (v5, Cyrillic = multibyte)	non-empty	fires
Hebrew/Arabic/Amharic/Urdu (WA)	0 bytes	never fires

• engineError stays 0; no log messages; no crash.
• CDasherModel::GetOffset() shows m_pLastOutput set (root path) but never advances — OutputTo(node) never receives an unseen node, so Do()/actions never run.
• Not geometry: swept x∈{40,100,700,760} and y∈{100..500} — no coordinate commits.
• Not RTL: Amharic (LTR) fails identically.

Pre-existing, not a #68 regression

Reproduced on pre-PR main (901e4d8, eager parsing) with the colour-fixed data — zero output there too. Nobody could see this before because these alphabets rendered invisible (#69 colour tokens) until da2e558.

Suspects

• The distinguishing parse shape is WA node elements whose multi-byte label becomes both Display and Text (no text attr), combined with duplicate symbols (Hebrew: 27, Arabic: 36, Amharic: 282 — every WA multibyte file has dups; WA English has none). The commit path (Reparent_root/Render→OutputTo) appears to depend on something the duplicate/multibyte map breaks — likely interaction with CAlphabetMap lookups during root rebuild (RebuildFindFromOffset text→symbol round-trip).
• Probe binaries and methodology available; DODUMP instrumentation point: CSymbolNode::Do() in AlphabetManager.cpp.

Impact

All WA-served RTL/Indic/Ethiopic/… languages are view-but-cannot-write. Combined with the 148-of-474 missing training corpora, the WA usability tail is: render ✓ (fixed), train (148 missing corpora), write ✗ (this issue).

[willwade]

Resolved — with a twist: this decomposed into two non-bugs and one real bug.

1. RTL alphabets were never broken. The crosshair mirrors to the LEFT edge for RTL orientation; steering from the left works fine (engine probes: Hebrew 134 bytes, Arabic 100 bytes). It looked unwritable because the glyphs rendered as tofu (GTK canvas font — fixed in Dasher-GTK#71), so there was nothing meaningful to aim at.
2. The real bug: informational warnings paused Dasher forever. FormatMessage hardwires the modal path, which pauses the input filter; the unpause path is only reachable after the model moves — impossible while paused. The trainer fires such a warning at startup for every alphabet lacking a (shipped) training corpus: Amharic, Adangbe, Azeri, and ~148 more. All rendered fine but froze on first input. Fixed in the attached PR: non-modal FormatInfoMessage for the trainer warnings (Amharic 0→81 B, Adangbe 0→44 B).
3. Follow-up kept open here: the modal-pause deadlock itself (onUnpause unreachable while paused) remains latent for genuinely modal messages — worth its own fix eventually.

[willwade]

Decomposed and resolved: RTL was never broken (mirror steering — see GTK PR #71 for the tofu that obscured it); the real bug (modal warning pauses forever on training-less alphabets) is fixed in PR fix/wa-multibyte-output; the latent modal-unpause deadlock is noted for follow-up.