New errors cropping up on iOS Safari

Hi. In the last month or so, I’ve noticed my ThreeJS project is breaking in Safari (on iPad Mini 2 and on my MacBook Air). I updated from v89 to 100, with no difference.
I’m seeing these errors:
ReferenceError: Can’t find variable: Float64Array three.min.js:725
TypeError: ‘undefined’ is not a constructor (evaluating ‘new THREE.TextureLoader()’) camera.js:4 (one of my scripts)
TypeError: ‘undefined’ is not a function (evaluating ‘this.forEachItems.bind(this)’) ink.js:3020
Not seeing any of this on Windows/Android.

What iOS version are you using? According to Can I Use, Float64Array should be supported since iOS Safari 5.0.

On the Mac, Safari 5.1, the iPad is running iOS 12.1.3.
So yeah, it doesn’t seem like these errors should be cropping up, but I’m seeing them in builds that had been working earlier in the Fall.

I updated my Mac. It’s now using Safari 5.1.7 and all those errors went away. I’m now getting errors for using querySelector for id rather than class; obviously unrelated to Three JS.
I updated further to 6.1.6 and I’m back to Three JS errors:
THREE.WebGLRenderer: error creating WebGL context. three.min.js:180:376
TypeError: ‘null’ is not an object (evaluating ‘a.getShaderPrecisionFormat’) three.min.js:31:169

Apparently you have to manually enable WebGL on Safari (6.1.6)? I did that, and am now past those errors and getting
ReferenceError: Can’t find variable: WeakMap three.min.js:82:383

According to the MDN, WeakMap is initially supported with Safari iOS 8.