Q:

Why are browsers failing to load some static content?

Using Magento 2.2.6.
I just installed a brand new install of 2.2.6 using Apache on OS X High Sierra, and with both Chrome and Firefox, after logging into the admin, the subnavigation does not work, and inspecting the page shows 12 js files have failed to load:
http://m226.local/pub/static/version1542310649/adminhtml/Magento/backend/en_US/mage/requirejs/mixins.js
http://m226.local/pub/static/version1542310649/adminhtml/Magento/backend/en_US/mage/adminhtml/globals.js

etc.
There are 70 odd other js files that load just fine:
http://m226.local/pub/static/version1542310649/adminhtml/Magento/backend/en_US/js/theme.js
http://m226.local/pub/static/version1542310649/adminhtml/Magento/backend/en_US/Magento_Ui/js/lib/knockout/bootstrap.js

etc.
When I curl the failed files, the file content comes back properly:
curl http://m226.local/pub/static/version1542310649/adminhtml/Magento/backend/en_US/mage/utils/strings.js
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
define([
    'underscore'
], function (_) {
    'use strict';

    var jsonRe = /^(?:\{[\w\W]*\}|\[[\w\W]*\])$/;

    return {

        /**
         * Attempts to convert string to one of the primitive values,
         * or to parse it as a valid json object.
         *
         * @param {String} str - String to be processed.
         * @returns {*}
         */
        castString: function (str) {
            try {

etc.
I've run rm -rf var/cache/* pub/static/adminhtml/* and static:content:deploy multiple times with no change.
Is there a reason these files are failing to load and if so how can I fix it?

A:

open your magento database and run this query to remove version
number from the path
insert core_config_data (config_id, scope, scope_id, path, value) values (null, 'default', 0, 'dev/static/sign', 0);
after this clear cache
rm -rf var/di/* var/generation/* var/cache/* var/log/* var/page_cache/* 
var/session/* var/view_preprocessed/* pub/static/*

Than deploy static content
php bin/magento setup:static-content:deploy -f

