To work around browser issues with unreliable cookie setting speed Adaptive Images now also checks the user agent string. If a desktop environment is detected, $mobile_first is automatically over-ridden to "FALSE". If not Adaptive Images will obey the configured value. This is a safety fallback and requires testing before I revert the default $mobile_first configured value to TRUE.
Fixed an issue where GD was present but did not always have the imageconvolution function available. Changed $mobile_first default to FALSE to avoid issues with unpredictable browser behaviour relating to race conditions between cookie setting and image requesting
…using an alternative JS snippet. (Thanks to Fabian Michael)
…ects of unfavourable race-condition outcomes. Stopped Firefox (and IE) from honouring $mobile_first: This is because both suffer from a race condition when setting the cookie. Sometimes it's set before <img> are requested, sometimes not. This could produce desktop websites with mobile versions on first page load. Changed the HTTP Cache Header from "public" to "private": This allows caches that are specific to one user (e.g., browser cache) to store the image in cache; shared caches (e.g., a proxy server) won't. This should avoid people behind proxies or other caching mechanisms experiencing wrongly sized images.
* fixing a possible cookie injection
And therefor renamed readme.htm back to instructions.htm