Create method to check if Fibers is enabled by flag DISABLE_FIBERS.

packages/meteor/helpers.js

@@ -171,3 +171,5 @@ function logErr(err) {
     );
   }
 }
+
+Meteor.isFibersEnabled = global.isFibersEnabled;

tools/static-assets/server/boot.js

@@ -14,6 +14,14 @@ var MIN_NODE_VERSION = 'v14.0.0';
 
 var hasOwn = Object.prototype.hasOwnProperty;
 
+//  For now it's a function to ensure we don't get a falsy value.
+//  Once we figure out the best place to create this EV (maybe it's here),
+//  it won't need to be a function anymore.
+
+global.isFibersEnabled = function () {
+  return !process.env.DISABLE_FIBERS;
+};
+
 if (require('semver').lt(process.version, MIN_NODE_VERSION)) {
   process.stderr.write(
     'Meteor requires Node ' + MIN_NODE_VERSION + ' or later.\n');