As seen on production:

First message (more below)

Error: {"message":"Argument 4 passed to CpChart\Chart\Draw::drawText() must be of the type array, boolean given, called in plugins/ImageGraph/StaticGraph/Exception.php on line 75","file":"/vendor/szymach/c-pchart/src/Chart/Draw.php","line":1186}

URL: index.php?module=API&method=ImageGraph.get&idSite=1&period=day&date=last10&apiModule=UserCountry&apiAction=getCountry&outputType=0&showLegend=1&fontSize=9&aliasedGraph=1&textColor=pfpszr9gse&backgroundColor=FFFFFF&gridColor=CCCCCC&legendAppendMetric=1&format=rss&token_auth=XYZANONYMIZED&translateColumnNames=1

FYI We received hundreds like this, so there may be othe payload that trigger it