Is your page indexable without JavaScript? One curl answers it — QuanticData SEO Audit API https://quanticdata.io/blog/how-to-perform-an-seo-audit/

qd-seo-audit.sh

#!/usr/bin/env bash
# Fetch a URL twice — as a no-JS bot and fully rendered — and show the difference.
# That diff is invisible in a browser: your eyes always see the rendered view.
#
#   export QD_API_KEY=qd_live_...
#   ./qd-seo-audit.sh https://example.com
#
# Needs curl and jq. $0.0012 a URL. https://quanticdata.io/seo-audit/
# Guide: https://quanticdata.io/blog/how-to-perform-an-seo-audit/
set -euo pipefail
: "${QD_API_KEY:?export QD_API_KEY — https://app.quanticdata.io/register}"
URL="${1:?usage: ./qd-seo-audit.sh <url>}"

curl -sS https://api.quanticdata.io/v1/seo-audit \
  -H "Authorization: Bearer $QD_API_KEY" \
  -H "Content-Type: application/json" \
  -d "$(jq -n --arg url "$URL" '{url: $url}')" \
| jq -r '
  if .type == "error" then "error: " + .message
  else .payload as $a |
    "\($a.url) -> \($a.finalUrl)\n",
    "                 no-JS bot                 rendered",
    "title       \($a.noJs.title // "-")   |   \($a.render.title // "-")",
    "h1          \($a.noJs.h1 // "-")   |   \($a.render.h1 // "-")",
    "words       \($a.noJs.wordCount)   |   \($a.render.wordCount)",
    "canonical   \($a.noJs.canonical // "MISSING")",
    "robots      \($a.meta.robots // "(none)")",
    "json-ld     \($a.meta.jsonldTypes | join(", "))",
    "",
    "findings:",
    ( $a.diff | to_entries[] | select(.value == true) |
      "  " + (
        if   .key == "contentOnlyInJs"      then "CRITICAL  the page is essentially blank without JavaScript"
        elif .key == "canonicalMissingNoJs" then "HIGH      canonical only appears after JS runs"
        elif .key == "h1OnlyInRender"       then "MEDIUM    no H1 in the served HTML"
        elif .key == "titleChanged"         then "MEDIUM    title is rewritten client-side"
        else "LOW       " + .key end ) ),
    ( if ($a.diff | to_entries | map(select(.value == true)) | length) == 0
      then "  none — the served HTML already carries the page" else empty end )
  end'