JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" name="myText" />

JavaScript

var pastValue, pastSelectionStart, pastSelectionEnd;

$("input").on("keydown", function() {
    pastValue          = this.value;
    pastSelectionStart = this.selectionStart;
    pastSelectionEnd   = this.selectionEnd;
}).on("input propertychange", function() {
    var regex = /^[0-9]+\.?[0-9]*$/;
					
    if (this.value.length > 0 && !regex.test(this.value)) {
        this.value          = pastValue;
        this.selectionStart = pastSelectionStart;
        this.selectionEnd   = pastSelectionEnd;
    }
});