I can't open the save file when downloading from Google Chrome 87, as the browser forces you to delete the file because "it is dangerous" with no way to keep the file.

Edit: The above behavior was because I had Safe Browsing on. Affected users may need to disable Safe Browsing for a brief moment in order to download the save game.

I can't open the save file when downloading from Google Chrome 87, as the browser forces you to delete the file because "it is dangerous" with no way to keep the file.

I'd suggest using a different browser if the behaviour can't be disabled.

Making some progress on this

Bug 1 is fixed here - LordAro@b427f30

Bug 2 is proving more tricky. Some notes of things I've found so far:

• Bug actually exists for all second (and third?) heliports, just only matters for the rotated airport with a missing tile at the top
• Helicopter has to actually descend to the heliport to trigger the bug - a helicopter taxiing to the heliport isn't enough.

I'm by no means certain of this, but I think this boils down to the "reuse" of AMED_SLOWTURN for flight and turning on the ground.

The first helipad of the intercontinental has some sort of offset - so the helicopter has to move a bit before loading/unloading, and its tile attribute is set to its actual tile position.

The second does not have any offset and it lands directly on the helipad. This means that for some reason that I'm not clear on, the vehicle's tile is set to the tile of the airport, rather than its actual position.

This appears to be the case for the majority of helipads (I've not tested them all), it's just that this one for the intercontinental is the exception. This only matters for the (rotated) intercontinental airport due to it being non-rectangular

From doing a bit of printf debugging, the assignment of the airport tile to the vehicle is here: https://github.com/OpenTTD/OpenTTD/blob/master/src/aircraft_cmd.cpp#L952-L953

tile is assigned from st->airport.tile at the start of the function.

The landing altitude in z could also be wrong for the same reason as the first sub-issue.

If it's not an oil rig, setting x and y from v->x_pos and v->y_pos and recalculating tile from that looks like it would work.

		if (st->airport.type != AT_OILRIG) {
			x = v->x_pos;
			y = v->y_pos;
			tile = TileVirtXY(x, y);
		}

		/* Vehicle is now at the airport. */
		v->tile = tile;

stops the crash, but I'm not sure whether that's really valid/sensible.