English rules dated at 2026/06/15 are not compatible with NVDA2026.1.1

[hjy1210]

1. In en/intent.rs, ther is a test intent_prob_x() with mathml as

<math>
    <msup intent='$op($arg)'>
        <mi arg='arg'>x</mi>
        <mi arg='op' intent='probability' mathvariant='normal'>P</mi>
    </msup></math>

under ClearSpeak, the expected output is probability of x.

I put above mathml in html file. The read out of above mathml with chrome+NVDA2026.1.1 with ClearSpeak+Verbose is probability math. Note, without of x.
Note, environment is chrome+NVDA2026.1.1 with en rules dated at 2026/06/15.

2. In en/chemistry.rs, there is a test mhchem_barbed_equilibrium() with mathml as

<math>
    <mrow data-mjx-texclass='ORD' data-chem-equation='14'>
      <mrow data-changed='added' data-chem-equation='3'>
        <mmultiscripts data-chem-formula='1'>
          <mi data-mjx-texclass='ORD' mathvariant='normal' data-chem-element='1'>H</mi>
          <mn data-mjx-texclass='ORD'>2</mn>
          <none></none>
        </mmultiscripts>
        <mo data-changed='added' data-function-guess='true'>&#x2063;</mo>
        <mrow data-changed='added' data-chem-equation='1'>
          <mo stretchy='false'>(</mo>
          <mi data-mjx-texclass='ORD' mathvariant='normal'>g</mi>
          <mo stretchy='false'>)</mo>
        </mrow>
      </mrow>
      <mo data-chem-equation-op='1'>+</mo>
      <mrow data-changed='added' data-chem-equation='10'>
        <mrow data-changed='added' data-chem-equation='3'>
          <mmultiscripts data-chem-formula='1'>
            <mi data-mjx-texclass='ORD' mathvariant='normal' data-chem-element='1'>I</mi>
            <mn data-mjx-texclass='ORD'>2</mn>
            <none></none>
          </mmultiscripts>
          <mo data-changed='added' data-function-guess='true'>&#x2063;</mo>
          <mrow data-changed='added' data-chem-equation='1'>
            <mo stretchy='false'>(</mo>
            <mi data-mjx-texclass='ORD' mathvariant='normal'>g</mi>
            <mo stretchy='false'>)</mo>
          </mrow>
        </mrow>
        <mo data-changed='added'>&#x2062;</mo>
        <mover data-mjx-texclass='REL'>
          <mrow data-mjx-texclass='ORD' depth='0' height='0' data-changed='added'>
            <mo data-mjx-texclass='ORD' stretchy='false'>↽</mo>
            <mo data-mjx-texclass='ORD'>-</mo>
          </mrow>
          <mrow data-mjx-texclass='ORD' displaystyle='false' scriptlevel='0' data-changed='added'>
            <mo data-mjx-texclass='ORD'>-</mo>
            <mo data-mjx-texclass='ORD' stretchy='false'>⇀</mo>
          </mrow>
        </mover>
        <mo data-changed='added'>&#x2062;</mo>
        <mn>2</mn>
        <mo data-changed='added'>&#x2062;</mo>
        <mrow data-changed='added' data-chem-equation='5'>
          <mi mathvariant='normal' data-chem-element='1'>H</mi>
          <mo data-changed='added'>&#x2063;</mo>
          <mi mathvariant='normal' data-chem-element='1'>I</mi>
          <mo data-changed='added' data-function-guess='true'>&#x2063;</mo>
          <mrow data-changed='added' data-chem-equation='1'>
            <mo stretchy='false'>(</mo>
            <mi data-mjx-texclass='ORD' mathvariant='normal'>g</mi>
            <mo stretchy='false'>)</mo>
          </mrow>
        </mrow>
      </mrow>
    </mrow>
  </math>

under SimpleSpeak and Terse Verbosity, the expected output is cap h, 2, gas; plus; cap i, 2, gas; is in equilibrium with, 2, cap h, cap i, gas.

I put above mathml in html file. The read out of above mathml with chrome+NVDA2026.1.1 with SimpleSpeak+Terse is cap h 2 gas plus cap i 2 gas "A2 2 cap h cap i gas math. Note, is in equilibrium with part is not correct.
Note, environment is chrome+NVDA2026.1.1 with en rules dated at 2026/06/15.

What is explanation? Both mathml have pass the unit test, the read out result are not as expected.