BTW, the point here is not to provide you with my preference for look/feel of the TiddlyWiki save button.
The point is to provide you with one possible starting point to customise the Save button to accommodate varied abilities.
Animation is the best way to get anybody's attention. There are all kinds of options other than blinking to get the attention of somebody with any kind of disability (attention-regulation, colour-blindness, seizures, etc.).
A visual cue that something needs to be done, it has to be easily noticeable yet not annoyingly distracting. So easily customised is key !