Vacation Rental Software Free Trial
Resources Blog
Booking Demo
Help Pages
How-To Videos
     Resources:  Blog

Bookerville provides many popular "widgets" that you can plop into any of your web-pages using a technique called iFrames. You can view all of these widgets here: Embeddable Widgets

The most popular of these is the Public Booking Calendar, but the Multi-Property Search, Public Master Calendar, rate tables, inquiry forms, and others are also very widely used by many property managers.

What Are 3rd-Party iFrames?

We are going to have to get a little technical here to explain this. iFrames have been around since at least the late 1990's. It's a simple way to automatically create a small box on your webpage that shows the content of another website.

This is very helpful for things like the Bookerville Public Booking Calendar for your property(ies). You plop in a simple iFrame tag into your webpages's HTML code, and the Bookerville Public Booking Calendar for that property appears right in that box in your webpage. And since Bookerville lets you choose custom accent colors, you can make this blend in pretty nicely into your page.

Widgets embedded as iFrames are much, much simpler and easier to install into your webpages than the alternative, which is hiring a professional web developer to build you a custom website (or modify your existing one) to make use of Bookerville's API. Embeddable widgets using iFrames are a much easier and much less expensive solution.

The iFrames you use to do this are called 3rd-party iFrames because they point to a different domain-name ( than the domain of your website.

So What's The Problem?

Over the past four years or so, the various browsers have started looking at 3rd-party iFrames as a security issue. I have still not read anything at all that really adequately explains the supposed security issues of 3rd-party iFrames, but there is a lot of material out there that asserts this to be true.

Because of this, browsers (Firefox, Chrome, Safari, Edge, and if you must, Internet Explorer) have been gradually making it harder and harder to effectively use 3rd-party iFrames. In fact, Chrome was the first to completely shut it down with the version that started rolling out about a year ago (early 2020).

The symptom of this is that the widget will still display ok when you first view your webpage, but upon trying to interact with it, you'll soon get the dreaded "session timeout" errors, and you can't make any progress.

Because of this, we started advising our clients to link to the various widgets instead of trying to embed them, because the link approach is not having any problems at all.

Then Why And How Are iFrames Back?

I don't know why - perhaps because of so many complaints from various organizations using 3rd-party iFrames legitimately? - but modern browsers are now allowing 3rd-party iFrames. As long as certain special "headers" are present in the content of the 3rd-party serving domain (, in this case), they will permit those 3rd-party iFrames to work as intended.

So we began investigating and testing this around May of 2020. It was very difficult and involving; the documentation on this is very cryptic, very vague. It also required migrating to newer versions of our technology stack, which in turn caused several other significant issues that had to be discovered through testing, developed around, and tested again. It has been a long, tedious, frustrating, and very expensive process.

But the fruits of this effort have shown that 3rd-party iFrames are indeed working again, even on the newest of the major browsers.

What Does This Mean For Me?

Most of you will probably not be affected at all. If you were one of the groups that switched your Bookerville widgets to be links instead of embedded iFrames, then you may wish to experiment with converting them back to embedded iFrames, if you prefer that solution. We advise that you try it with only one or two properties, test it thoroughly, and even then let that test property prove that it works well for a variety of guests for a few weeks before switching all your properties back to embedded iFrames.

When testing: it's always best to test your widgets when positively signed out of your Bookerville account. This ensures that you are most-closely mimicking the same experience of an anonymous guest to your website.

Will iFrames Work Forever Now?

That is the big question isn't it? We sure hope so - but this contentious technology has gone back and forth over the years, with various browser brands choosing to not support them, only to reverse their stance a year later, etc. It's been a frustrating situation for a long time.

What Bookerville is still recommending to clients is to just link to these widgets instead of embedding them. Links are a much more reliable way of achieving integration: the various widgets look and work their best when they are running in their own, stand-alone page, and links provide that ideal context for them. Also, by not embedding them into your page you will be immune to the fickle tantrums of the browser gods in the future.

As always, contact us if you need help, or have questions/concerns about any of this.

Reply »


Vacation Rental Software Booking Demo
Vacation Rental Software Free Trial